* Step 1: Sum WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict TRS:
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            flattensort(@t) -> insertionsort(flatten(@t))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1} / {#0/0,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0
            ,::/2,leaf/0,nil/0,node/3}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt,#compare,#less,append,append#1,flatten,flatten#1
            ,flattensort,insert,insert#1,insert#2,insertionsort,insertionsort#1} and constructors {#0,#EQ,#GT,#LT,#false
            ,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Sum {left = someStrategy, right = someStrategy}
    + Details:
        ()
* Step 2: DependencyPairs WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict TRS:
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            flattensort(@t) -> insertionsort(flatten(@t))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1} / {#0/0,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0
            ,::/2,leaf/0,nil/0,node/3}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt,#compare,#less,append,append#1,flatten,flatten#1
            ,flattensort,insert,insert#1,insert#2,insertionsort,insertionsort#1} and constructors {#0,#EQ,#GT,#LT,#false
            ,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        DependencyPairs {dpKind_ = DT}
    + Details:
        We add the following dependency tuples:
        
        Strict DPs
          #less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y))
          append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
          append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
          append#1#(nil(),@l2) -> c_4()
          flatten#(@t) -> c_5(flatten#1#(@t))
          flatten#1#(leaf()) -> c_6()
          flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                             ,append#(flatten(@t1),flatten(@t2))
                                             ,flatten#(@t1)
                                             ,flatten#(@t2))
          flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
          insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
          insert#1#(nil(),@x) -> c_11()
          insert#2#(#false(),@x,@y,@ys) -> c_12()
          insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          insertionsort#1#(nil()) -> c_16()
        Weak DPs
          #cklt#(#EQ()) -> c_17()
          #cklt#(#GT()) -> c_18()
          #cklt#(#LT()) -> c_19()
          #compare#(#0(),#0()) -> c_20()
          #compare#(#0(),#neg(@y)) -> c_21()
          #compare#(#0(),#pos(@y)) -> c_22()
          #compare#(#0(),#s(@y)) -> c_23()
          #compare#(#neg(@x),#0()) -> c_24()
          #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x))
          #compare#(#neg(@x),#pos(@y)) -> c_26()
          #compare#(#pos(@x),#0()) -> c_27()
          #compare#(#pos(@x),#neg(@y)) -> c_28()
          #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y))
          #compare#(#s(@x),#0()) -> c_30()
          #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y))
        
        and mark the set of starting terms.
* Step 3: UsableRules WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            #less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y))
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
            append#1#(nil(),@l2) -> c_4()
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(leaf()) -> c_6()
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
            insert#1#(nil(),@x) -> c_11()
            insert#2#(#false(),@x,@y,@ys) -> c_12()
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
            insertionsort#1#(nil()) -> c_16()
        - Weak DPs:
            #cklt#(#EQ()) -> c_17()
            #cklt#(#GT()) -> c_18()
            #cklt#(#LT()) -> c_19()
            #compare#(#0(),#0()) -> c_20()
            #compare#(#0(),#neg(@y)) -> c_21()
            #compare#(#0(),#pos(@y)) -> c_22()
            #compare#(#0(),#s(@y)) -> c_23()
            #compare#(#neg(@x),#0()) -> c_24()
            #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x))
            #compare#(#neg(@x),#pos(@y)) -> c_26()
            #compare#(#pos(@x),#0()) -> c_27()
            #compare#(#pos(@x),#neg(@y)) -> c_28()
            #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y))
            #compare#(#s(@x),#0()) -> c_30()
            #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            flattensort(@t) -> insertionsort(flatten(@t))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/2,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        UsableRules
    + Details:
        We replace rewrite rules by usable rules:
          #cklt(#EQ()) -> #false()
          #cklt(#GT()) -> #false()
          #cklt(#LT()) -> #true()
          #compare(#0(),#0()) -> #EQ()
          #compare(#0(),#neg(@y)) -> #GT()
          #compare(#0(),#pos(@y)) -> #LT()
          #compare(#0(),#s(@y)) -> #LT()
          #compare(#neg(@x),#0()) -> #LT()
          #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
          #compare(#neg(@x),#pos(@y)) -> #LT()
          #compare(#pos(@x),#0()) -> #GT()
          #compare(#pos(@x),#neg(@y)) -> #GT()
          #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
          #compare(#s(@x),#0()) -> #GT()
          #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
          #less(@x,@y) -> #cklt(#compare(@x,@y))
          append(@l1,@l2) -> append#1(@l1,@l2)
          append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
          append#1(nil(),@l2) -> @l2
          flatten(@t) -> flatten#1(@t)
          flatten#1(leaf()) -> nil()
          flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
          insert(@x,@l) -> insert#1(@l,@x)
          insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
          insert#1(nil(),@x) -> ::(@x,nil())
          insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
          insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
          insertionsort(@l) -> insertionsort#1(@l)
          insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
          insertionsort#1(nil()) -> nil()
          #cklt#(#EQ()) -> c_17()
          #cklt#(#GT()) -> c_18()
          #cklt#(#LT()) -> c_19()
          #compare#(#0(),#0()) -> c_20()
          #compare#(#0(),#neg(@y)) -> c_21()
          #compare#(#0(),#pos(@y)) -> c_22()
          #compare#(#0(),#s(@y)) -> c_23()
          #compare#(#neg(@x),#0()) -> c_24()
          #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x))
          #compare#(#neg(@x),#pos(@y)) -> c_26()
          #compare#(#pos(@x),#0()) -> c_27()
          #compare#(#pos(@x),#neg(@y)) -> c_28()
          #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y))
          #compare#(#s(@x),#0()) -> c_30()
          #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y))
          #less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y))
          append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
          append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
          append#1#(nil(),@l2) -> c_4()
          flatten#(@t) -> c_5(flatten#1#(@t))
          flatten#1#(leaf()) -> c_6()
          flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                             ,append#(flatten(@t1),flatten(@t2))
                                             ,flatten#(@t1)
                                             ,flatten#(@t2))
          flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
          insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
          insert#1#(nil(),@x) -> c_11()
          insert#2#(#false(),@x,@y,@ys) -> c_12()
          insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          insertionsort#1#(nil()) -> c_16()
* Step 4: PredecessorEstimation WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            #less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y))
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
            append#1#(nil(),@l2) -> c_4()
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(leaf()) -> c_6()
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
            insert#1#(nil(),@x) -> c_11()
            insert#2#(#false(),@x,@y,@ys) -> c_12()
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
            insertionsort#1#(nil()) -> c_16()
        - Weak DPs:
            #cklt#(#EQ()) -> c_17()
            #cklt#(#GT()) -> c_18()
            #cklt#(#LT()) -> c_19()
            #compare#(#0(),#0()) -> c_20()
            #compare#(#0(),#neg(@y)) -> c_21()
            #compare#(#0(),#pos(@y)) -> c_22()
            #compare#(#0(),#s(@y)) -> c_23()
            #compare#(#neg(@x),#0()) -> c_24()
            #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x))
            #compare#(#neg(@x),#pos(@y)) -> c_26()
            #compare#(#pos(@x),#0()) -> c_27()
            #compare#(#pos(@x),#neg(@y)) -> c_28()
            #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y))
            #compare#(#s(@x),#0()) -> c_30()
            #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/2,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        PredecessorEstimation {onSelection = all simple predecessor estimation selector}
    + Details:
        We estimate the number of application of
          {1,4,6,11,12,16}
        by application of
          Pre({1,4,6,11,12,16}) = {2,5,9,10,14}.
        Here rules are labelled as follows:
          1: #less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y))
          2: append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
          3: append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
          4: append#1#(nil(),@l2) -> c_4()
          5: flatten#(@t) -> c_5(flatten#1#(@t))
          6: flatten#1#(leaf()) -> c_6()
          7: flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                ,append#(flatten(@t1),flatten(@t2))
                                                ,flatten#(@t1)
                                                ,flatten#(@t2))
          8: flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
          9: insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          10: insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
          11: insert#1#(nil(),@x) -> c_11()
          12: insert#2#(#false(),@x,@y,@ys) -> c_12()
          13: insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          14: insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          15: insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          16: insertionsort#1#(nil()) -> c_16()
          17: #cklt#(#EQ()) -> c_17()
          18: #cklt#(#GT()) -> c_18()
          19: #cklt#(#LT()) -> c_19()
          20: #compare#(#0(),#0()) -> c_20()
          21: #compare#(#0(),#neg(@y)) -> c_21()
          22: #compare#(#0(),#pos(@y)) -> c_22()
          23: #compare#(#0(),#s(@y)) -> c_23()
          24: #compare#(#neg(@x),#0()) -> c_24()
          25: #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x))
          26: #compare#(#neg(@x),#pos(@y)) -> c_26()
          27: #compare#(#pos(@x),#0()) -> c_27()
          28: #compare#(#pos(@x),#neg(@y)) -> c_28()
          29: #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y))
          30: #compare#(#s(@x),#0()) -> c_30()
          31: #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y))
* Step 5: RemoveWeakSuffixes WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak DPs:
            #cklt#(#EQ()) -> c_17()
            #cklt#(#GT()) -> c_18()
            #cklt#(#LT()) -> c_19()
            #compare#(#0(),#0()) -> c_20()
            #compare#(#0(),#neg(@y)) -> c_21()
            #compare#(#0(),#pos(@y)) -> c_22()
            #compare#(#0(),#s(@y)) -> c_23()
            #compare#(#neg(@x),#0()) -> c_24()
            #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x))
            #compare#(#neg(@x),#pos(@y)) -> c_26()
            #compare#(#pos(@x),#0()) -> c_27()
            #compare#(#pos(@x),#neg(@y)) -> c_28()
            #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y))
            #compare#(#s(@x),#0()) -> c_30()
            #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y))
            #less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y))
            append#1#(nil(),@l2) -> c_4()
            flatten#1#(leaf()) -> c_6()
            insert#1#(nil(),@x) -> c_11()
            insert#2#(#false(),@x,@y,@ys) -> c_12()
            insertionsort#1#(nil()) -> c_16()
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/2,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        RemoveWeakSuffixes
    + Details:
        Consider the dependency graph
          1:S:append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
             -->_1 append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2)):2
             -->_1 append#1#(nil(),@l2) -> c_4():27
          
          2:S:append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
          
          3:S:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                      ,append#(flatten(@t1),flatten(@t2))
                                                      ,flatten#(@t1)
                                                      ,flatten#(@t2)):4
             -->_1 flatten#1#(leaf()) -> c_6():28
          
          4:S:flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
             -->_4 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_3 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_2 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
          
          5:S:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):9
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):3
          
          6:S:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x)):7
             -->_1 insert#1#(nil(),@x) -> c_11():29
          
          7:S:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
             -->_2 #less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y)):26
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):8
             -->_1 insert#2#(#false(),@x,@y,@ys) -> c_12():30
          
          8:S:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):6
          
          9:S:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):10
             -->_1 insertionsort#1#(nil()) -> c_16():31
          
          10:S:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):9
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):6
          
          11:W:#cklt#(#EQ()) -> c_17()
             
          
          12:W:#cklt#(#GT()) -> c_18()
             
          
          13:W:#cklt#(#LT()) -> c_19()
             
          
          14:W:#compare#(#0(),#0()) -> c_20()
             
          
          15:W:#compare#(#0(),#neg(@y)) -> c_21()
             
          
          16:W:#compare#(#0(),#pos(@y)) -> c_22()
             
          
          17:W:#compare#(#0(),#s(@y)) -> c_23()
             
          
          18:W:#compare#(#neg(@x),#0()) -> c_24()
             
          
          19:W:#compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x))
             -->_1 #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y)):25
             -->_1 #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y)):23
             -->_1 #compare#(#s(@x),#0()) -> c_30():24
             -->_1 #compare#(#pos(@x),#neg(@y)) -> c_28():22
             -->_1 #compare#(#pos(@x),#0()) -> c_27():21
             -->_1 #compare#(#neg(@x),#pos(@y)) -> c_26():20
             -->_1 #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x)):19
             -->_1 #compare#(#neg(@x),#0()) -> c_24():18
             -->_1 #compare#(#0(),#s(@y)) -> c_23():17
             -->_1 #compare#(#0(),#pos(@y)) -> c_22():16
             -->_1 #compare#(#0(),#neg(@y)) -> c_21():15
             -->_1 #compare#(#0(),#0()) -> c_20():14
          
          20:W:#compare#(#neg(@x),#pos(@y)) -> c_26()
             
          
          21:W:#compare#(#pos(@x),#0()) -> c_27()
             
          
          22:W:#compare#(#pos(@x),#neg(@y)) -> c_28()
             
          
          23:W:#compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y))
             -->_1 #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y)):25
             -->_1 #compare#(#s(@x),#0()) -> c_30():24
             -->_1 #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y)):23
             -->_1 #compare#(#pos(@x),#neg(@y)) -> c_28():22
             -->_1 #compare#(#pos(@x),#0()) -> c_27():21
             -->_1 #compare#(#neg(@x),#pos(@y)) -> c_26():20
             -->_1 #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x)):19
             -->_1 #compare#(#neg(@x),#0()) -> c_24():18
             -->_1 #compare#(#0(),#s(@y)) -> c_23():17
             -->_1 #compare#(#0(),#pos(@y)) -> c_22():16
             -->_1 #compare#(#0(),#neg(@y)) -> c_21():15
             -->_1 #compare#(#0(),#0()) -> c_20():14
          
          24:W:#compare#(#s(@x),#0()) -> c_30()
             
          
          25:W:#compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y))
             -->_1 #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y)):25
             -->_1 #compare#(#s(@x),#0()) -> c_30():24
             -->_1 #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y)):23
             -->_1 #compare#(#pos(@x),#neg(@y)) -> c_28():22
             -->_1 #compare#(#pos(@x),#0()) -> c_27():21
             -->_1 #compare#(#neg(@x),#pos(@y)) -> c_26():20
             -->_1 #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x)):19
             -->_1 #compare#(#neg(@x),#0()) -> c_24():18
             -->_1 #compare#(#0(),#s(@y)) -> c_23():17
             -->_1 #compare#(#0(),#pos(@y)) -> c_22():16
             -->_1 #compare#(#0(),#neg(@y)) -> c_21():15
             -->_1 #compare#(#0(),#0()) -> c_20():14
          
          26:W:#less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y))
             -->_2 #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y)):25
             -->_2 #compare#(#s(@x),#0()) -> c_30():24
             -->_2 #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y)):23
             -->_2 #compare#(#pos(@x),#neg(@y)) -> c_28():22
             -->_2 #compare#(#pos(@x),#0()) -> c_27():21
             -->_2 #compare#(#neg(@x),#pos(@y)) -> c_26():20
             -->_2 #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x)):19
             -->_2 #compare#(#neg(@x),#0()) -> c_24():18
             -->_2 #compare#(#0(),#s(@y)) -> c_23():17
             -->_2 #compare#(#0(),#pos(@y)) -> c_22():16
             -->_2 #compare#(#0(),#neg(@y)) -> c_21():15
             -->_2 #compare#(#0(),#0()) -> c_20():14
             -->_1 #cklt#(#LT()) -> c_19():13
             -->_1 #cklt#(#GT()) -> c_18():12
             -->_1 #cklt#(#EQ()) -> c_17():11
          
          27:W:append#1#(nil(),@l2) -> c_4()
             
          
          28:W:flatten#1#(leaf()) -> c_6()
             
          
          29:W:insert#1#(nil(),@x) -> c_11()
             
          
          30:W:insert#2#(#false(),@x,@y,@ys) -> c_12()
             
          
          31:W:insertionsort#1#(nil()) -> c_16()
             
          
        The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed.
          31: insertionsort#1#(nil()) -> c_16()
          29: insert#1#(nil(),@x) -> c_11()
          30: insert#2#(#false(),@x,@y,@ys) -> c_12()
          26: #less#(@x,@y) -> c_1(#cklt#(#compare(@x,@y)),#compare#(@x,@y))
          11: #cklt#(#EQ()) -> c_17()
          12: #cklt#(#GT()) -> c_18()
          13: #cklt#(#LT()) -> c_19()
          25: #compare#(#s(@x),#s(@y)) -> c_31(#compare#(@x,@y))
          23: #compare#(#pos(@x),#pos(@y)) -> c_29(#compare#(@x,@y))
          19: #compare#(#neg(@x),#neg(@y)) -> c_25(#compare#(@y,@x))
          14: #compare#(#0(),#0()) -> c_20()
          15: #compare#(#0(),#neg(@y)) -> c_21()
          16: #compare#(#0(),#pos(@y)) -> c_22()
          17: #compare#(#0(),#s(@y)) -> c_23()
          18: #compare#(#neg(@x),#0()) -> c_24()
          20: #compare#(#neg(@x),#pos(@y)) -> c_26()
          21: #compare#(#pos(@x),#0()) -> c_27()
          22: #compare#(#pos(@x),#neg(@y)) -> c_28()
          24: #compare#(#s(@x),#0()) -> c_30()
          28: flatten#1#(leaf()) -> c_6()
          27: append#1#(nil(),@l2) -> c_4()
* Step 6: SimplifyRHS WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/2,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        SimplifyRHS
    + Details:
        Consider the dependency graph
          1:S:append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
             -->_1 append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2)):2
          
          2:S:append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
          
          3:S:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                      ,append#(flatten(@t1),flatten(@t2))
                                                      ,flatten#(@t1)
                                                      ,flatten#(@t2)):4
          
          4:S:flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
             -->_4 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_3 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_2 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
          
          5:S:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):9
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):3
          
          6:S:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x)):7
          
          7:S:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys),#less#(@y,@x))
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):8
          
          8:S:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):6
          
          9:S:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):10
          
          10:S:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):9
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):6
          
        Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified:
          insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
* Step 7: Decompose WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Decompose {onSelection = all cycle independent sub-graph, withBound = RelativeAdd}
    + Details:
        We analyse the complexity of following sub-problems (R) and (S).
        Problem (S) is obtained from the input problem by shifting strict rules from (R) into the weak component.
        
        Problem (R)
          - Strict DPs:
              append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
              append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
          - Weak DPs:
              flatten#(@t) -> c_5(flatten#1#(@t))
              flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
              flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
              insert#(@x,@l) -> c_9(insert#1#(@l,@x))
              insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
              insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
              insertionsort#(@l) -> c_14(insertionsort#1#(@l))
              insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          - Weak TRS:
              #cklt(#EQ()) -> #false()
              #cklt(#GT()) -> #false()
              #cklt(#LT()) -> #true()
              #compare(#0(),#0()) -> #EQ()
              #compare(#0(),#neg(@y)) -> #GT()
              #compare(#0(),#pos(@y)) -> #LT()
              #compare(#0(),#s(@y)) -> #LT()
              #compare(#neg(@x),#0()) -> #LT()
              #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
              #compare(#neg(@x),#pos(@y)) -> #LT()
              #compare(#pos(@x),#0()) -> #GT()
              #compare(#pos(@x),#neg(@y)) -> #GT()
              #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
              #compare(#s(@x),#0()) -> #GT()
              #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
              #less(@x,@y) -> #cklt(#compare(@x,@y))
              append(@l1,@l2) -> append#1(@l1,@l2)
              append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
              append#1(nil(),@l2) -> @l2
              flatten(@t) -> flatten#1(@t)
              flatten#1(leaf()) -> nil()
              flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
              insert(@x,@l) -> insert#1(@l,@x)
              insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
              insert#1(nil(),@x) -> ::(@x,nil())
              insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
              insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
              insertionsort(@l) -> insertionsort#1(@l)
              insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
              insertionsort#1(nil()) -> nil()
          - Signature:
              {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
              ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2
              ,flatten#/1,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1
              ,insertionsort#1#/1} / {#0/0,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0
              ,node/3,c_1/2,c_2/1,c_3/1,c_4/0,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2
              ,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0
              ,c_31/1}
          - Obligation:
              innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
              ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
              ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
        
        Problem (S)
          - Strict DPs:
              flatten#(@t) -> c_5(flatten#1#(@t))
              flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
              flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
              insert#(@x,@l) -> c_9(insert#1#(@l,@x))
              insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
              insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
              insertionsort#(@l) -> c_14(insertionsort#1#(@l))
              insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          - Weak DPs:
              append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
              append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
          - Weak TRS:
              #cklt(#EQ()) -> #false()
              #cklt(#GT()) -> #false()
              #cklt(#LT()) -> #true()
              #compare(#0(),#0()) -> #EQ()
              #compare(#0(),#neg(@y)) -> #GT()
              #compare(#0(),#pos(@y)) -> #LT()
              #compare(#0(),#s(@y)) -> #LT()
              #compare(#neg(@x),#0()) -> #LT()
              #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
              #compare(#neg(@x),#pos(@y)) -> #LT()
              #compare(#pos(@x),#0()) -> #GT()
              #compare(#pos(@x),#neg(@y)) -> #GT()
              #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
              #compare(#s(@x),#0()) -> #GT()
              #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
              #less(@x,@y) -> #cklt(#compare(@x,@y))
              append(@l1,@l2) -> append#1(@l1,@l2)
              append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
              append#1(nil(),@l2) -> @l2
              flatten(@t) -> flatten#1(@t)
              flatten#1(leaf()) -> nil()
              flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
              insert(@x,@l) -> insert#1(@l,@x)
              insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
              insert#1(nil(),@x) -> ::(@x,nil())
              insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
              insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
              insertionsort(@l) -> insertionsort#1(@l)
              insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
              insertionsort#1(nil()) -> nil()
          - Signature:
              {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
              ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2
              ,flatten#/1,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1
              ,insertionsort#1#/1} / {#0/0,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0
              ,node/3,c_1/2,c_2/1,c_3/1,c_4/0,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2
              ,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0
              ,c_31/1}
          - Obligation:
              innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
              ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
              ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
** Step 7.a:1: RemoveWeakSuffixes WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
        - Weak DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        RemoveWeakSuffixes
    + Details:
        Consider the dependency graph
          1:S:append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
             -->_1 append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2)):2
          
          2:S:append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
          
          3:W:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                      ,append#(flatten(@t1),flatten(@t2))
                                                      ,flatten#(@t1)
                                                      ,flatten#(@t2)):4
          
          4:W:flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
             -->_2 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
             -->_4 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_3 flatten#(@t) -> c_5(flatten#1#(@t)):3
          
          5:W:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):9
          
          6:W:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys)):7
          
          7:W:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):8
          
          8:W:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):6
          
          9:W:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):10
          
          10:W:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):6
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):9
          
        The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed.
          9: insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          10: insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          6: insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          8: insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          7: insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
** Step 7.a:2: SimplifyRHS WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
        - Weak DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        SimplifyRHS
    + Details:
        Consider the dependency graph
          1:S:append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
             -->_1 append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2)):2
          
          2:S:append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
          
          3:W:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                      ,append#(flatten(@t1),flatten(@t2))
                                                      ,flatten#(@t1)
                                                      ,flatten#(@t2)):4
          
          4:W:flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
             -->_2 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
             -->_4 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_3 flatten#(@t) -> c_5(flatten#1#(@t)):3
          
          5:W:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):3
          
        Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified:
          flattensort#(@t) -> c_8(flatten#(@t))
** Step 7.a:3: UsableRules WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
        - Weak DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(flatten#(@t))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        UsableRules
    + Details:
        We replace rewrite rules by usable rules:
          append(@l1,@l2) -> append#1(@l1,@l2)
          append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
          append#1(nil(),@l2) -> @l2
          flatten(@t) -> flatten#1(@t)
          flatten#1(leaf()) -> nil()
          flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
          append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
          append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
          flatten#(@t) -> c_5(flatten#1#(@t))
          flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                             ,append#(flatten(@t1),flatten(@t2))
                                             ,flatten#(@t1)
                                             ,flatten#(@t2))
          flattensort#(@t) -> c_8(flatten#(@t))
** Step 7.a:4: PredecessorEstimationCP WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
        - Weak DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(flatten#(@t))
        - Weak TRS:
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        PredecessorEstimationCP {onSelectionCP = any intersect of rules of CDG leaf and strict-rules, withComplexityPair = NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing}}
    + Details:
        We first use the processor NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing} to orient following rules strictly:
          1: append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
          
        Consider the set of all dependency pairs
          1: append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
          2: append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
          3: flatten#(@t) -> c_5(flatten#1#(@t))
          4: flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                ,append#(flatten(@t1),flatten(@t2))
                                                ,flatten#(@t1)
                                                ,flatten#(@t2))
          5: flattensort#(@t) -> c_8(flatten#(@t))
        Processor NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing}induces the complexity certificateTIME (?,O(n^2))
        SPACE(?,?)on application of the dependency pairs
          {1}
        These cover all (indirect) predecessors of dependency pairs
          {1,2,5}
        their number of applications is equally bounded.
        The dependency pairs are shifted into the weak component.
*** Step 7.a:4.a:1: NaturalPI WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
        - Weak DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(flatten#(@t))
        - Weak TRS:
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Just first alternative for predecessorEstimation on any intersect of rules of CDG leaf and strict-rules}
    + Details:
        We apply a polynomial interpretation of kind constructor-based(mixed(2)):
        The following argument positions are considered usable:
          uargs(c_2) = {1},
          uargs(c_3) = {1},
          uargs(c_5) = {1},
          uargs(c_7) = {1,2,3,4},
          uargs(c_8) = {1}
        
        Following symbols are considered usable:
          {append,append#1,flatten,flatten#1,#cklt#,#compare#,#less#,append#,append#1#,flatten#,flatten#1#
          ,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#}
        TcT has computed the following interpretation:
                        p(#0) = 0                
                       p(#EQ) = 0                
                       p(#GT) = 0                
                       p(#LT) = 0                
                     p(#cklt) = 0                
                  p(#compare) = 0                
                    p(#false) = 0                
                     p(#less) = 0                
                      p(#neg) = 0                
                      p(#pos) = 0                
                        p(#s) = 0                
                     p(#true) = 0                
                        p(::) = 1 + x2           
                    p(append) = x1 + x2          
                  p(append#1) = x1 + x2          
                   p(flatten) = x1               
                 p(flatten#1) = x1               
               p(flattensort) = 0                
                    p(insert) = 0                
                  p(insert#1) = 0                
                  p(insert#2) = 0                
             p(insertionsort) = 0                
           p(insertionsort#1) = 0                
                      p(leaf) = 1                
                       p(nil) = 1                
                      p(node) = 1 + x1 + x2 + x3 
                    p(#cklt#) = 0                
                 p(#compare#) = 0                
                    p(#less#) = 0                
                   p(append#) = 1 + x1           
                 p(append#1#) = x1               
                  p(flatten#) = x1 + x1^2        
                p(flatten#1#) = x1 + x1^2        
              p(flattensort#) = x1 + x1^2        
                   p(insert#) = 0                
                 p(insert#1#) = 0                
                 p(insert#2#) = 0                
            p(insertionsort#) = 0                
          p(insertionsort#1#) = 0                
                       p(c_1) = 0                
                       p(c_2) = x1               
                       p(c_3) = x1               
                       p(c_4) = 0                
                       p(c_5) = x1               
                       p(c_6) = 0                
                       p(c_7) = x1 + x2 + x3 + x4
                       p(c_8) = x1               
                       p(c_9) = 0                
                      p(c_10) = 0                
                      p(c_11) = 0                
                      p(c_12) = 0                
                      p(c_13) = 0                
                      p(c_14) = 0                
                      p(c_15) = 0                
                      p(c_16) = 0                
                      p(c_17) = 0                
                      p(c_18) = 0                
                      p(c_19) = 0                
                      p(c_20) = 0                
                      p(c_21) = 0                
                      p(c_22) = 0                
                      p(c_23) = 0                
                      p(c_24) = 0                
                      p(c_25) = 0                
                      p(c_26) = 0                
                      p(c_27) = 0                
                      p(c_28) = 0                
                      p(c_29) = 0                
                      p(c_30) = 0                
                      p(c_31) = 0                
        
        Following rules are strictly oriented:
        append#(@l1,@l2) = 1 + @l1                
                         > @l1                    
                         = c_2(append#1#(@l1,@l2))
        
        
        Following rules are (at-least) weakly oriented:
           append#1#(::(@x,@xs),@l2) =  1 + @xs                                                                          
                                     >= 1 + @xs                                                                          
                                     =  c_3(append#(@xs,@l2))                                                            
        
                        flatten#(@t) =  @t + @t^2                                                                        
                                     >= @t + @t^2                                                                        
                                     =  c_5(flatten#1#(@t))                                                              
        
        flatten#1#(node(@l,@t1,@t2)) =  2 + 3*@l + 2*@l*@t1 + 2*@l*@t2 + @l^2 + 3*@t1 + 2*@t1*@t2 + @t1^2 + 3*@t2 + @t2^2
                                     >= 2 + @l + 2*@t1 + @t1^2 + @t2 + @t2^2                                             
                                     =  c_7(append#(@l,append(flatten(@t1),flatten(@t2)))                                
                                           ,append#(flatten(@t1),flatten(@t2))                                           
                                           ,flatten#(@t1)                                                                
                                           ,flatten#(@t2))                                                               
        
                    flattensort#(@t) =  @t + @t^2                                                                        
                                     >= @t + @t^2                                                                        
                                     =  c_8(flatten#(@t))                                                                
        
                     append(@l1,@l2) =  @l1 + @l2                                                                        
                                     >= @l1 + @l2                                                                        
                                     =  append#1(@l1,@l2)                                                                
        
            append#1(::(@x,@xs),@l2) =  1 + @l2 + @xs                                                                    
                                     >= 1 + @l2 + @xs                                                                    
                                     =  ::(@x,append(@xs,@l2))                                                           
        
                 append#1(nil(),@l2) =  1 + @l2                                                                          
                                     >= @l2                                                                              
                                     =  @l2                                                                              
        
                         flatten(@t) =  @t                                                                               
                                     >= @t                                                                               
                                     =  flatten#1(@t)                                                                    
        
                   flatten#1(leaf()) =  1                                                                                
                                     >= 1                                                                                
                                     =  nil()                                                                            
        
         flatten#1(node(@l,@t1,@t2)) =  1 + @l + @t1 + @t2                                                               
                                     >= @l + @t1 + @t2                                                                   
                                     =  append(@l,append(flatten(@t1),flatten(@t2)))                                     
        
*** Step 7.a:4.a:2: Assumption WORST_CASE(?,O(1))
    + Considered Problem:
        - Strict DPs:
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
        - Weak DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(flatten#(@t))
        - Weak TRS:
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Assumption {assumed = Certificate {spaceUB = Unknown, spaceLB = Unknown, timeUB = Poly (Just 0), timeLB = Unknown}}
    + Details:
        ()

*** Step 7.a:4.b:1: RemoveWeakSuffixes WORST_CASE(?,O(1))
    + Considered Problem:
        - Weak DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(flatten#(@t))
        - Weak TRS:
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        RemoveWeakSuffixes
    + Details:
        Consider the dependency graph
          1:W:append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
             -->_1 append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2)):2
          
          2:W:append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
          
          3:W:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                      ,append#(flatten(@t1),flatten(@t2))
                                                      ,flatten#(@t1)
                                                      ,flatten#(@t2)):4
          
          4:W:flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
             -->_4 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_3 flatten#(@t) -> c_5(flatten#1#(@t)):3
             -->_2 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):1
          
          5:W:flattensort#(@t) -> c_8(flatten#(@t))
             -->_1 flatten#(@t) -> c_5(flatten#1#(@t)):3
          
        The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed.
          5: flattensort#(@t) -> c_8(flatten#(@t))
          3: flatten#(@t) -> c_5(flatten#1#(@t))
          4: flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                ,append#(flatten(@t1),flatten(@t2))
                                                ,flatten#(@t1)
                                                ,flatten#(@t2))
          1: append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
          2: append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
*** Step 7.a:4.b:2: EmptyProcessor WORST_CASE(?,O(1))
    + Considered Problem:
        - Weak TRS:
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        EmptyProcessor
    + Details:
        The problem is already closed. The intended complexity is O(1).

** Step 7.b:1: RemoveWeakSuffixes WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak DPs:
            append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
            append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        RemoveWeakSuffixes
    + Details:
        Consider the dependency graph
          1:S:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                      ,append#(flatten(@t1),flatten(@t2))
                                                      ,flatten#(@t1)
                                                      ,flatten#(@t2)):2
          
          2:S:flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
             -->_2 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):9
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):9
             -->_4 flatten#(@t) -> c_5(flatten#1#(@t)):1
             -->_3 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
          3:S:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):7
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
          4:S:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys)):5
          
          5:S:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):6
          
          6:S:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):4
          
          7:S:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):8
          
          8:S:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):7
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):4
          
          9:W:append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
             -->_1 append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2)):10
          
          10:W:append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
             -->_1 append#(@l1,@l2) -> c_2(append#1#(@l1,@l2)):9
          
        The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed.
          9: append#(@l1,@l2) -> c_2(append#1#(@l1,@l2))
          10: append#1#(::(@x,@xs),@l2) -> c_3(append#(@xs,@l2))
** Step 7.b:2: SimplifyRHS WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                               ,append#(flatten(@t1),flatten(@t2))
                                               ,flatten#(@t1)
                                               ,flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/4,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        SimplifyRHS
    + Details:
        Consider the dependency graph
          1:S:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                      ,append#(flatten(@t1),flatten(@t2))
                                                      ,flatten#(@t1)
                                                      ,flatten#(@t2)):2
          
          2:S:flatten#1#(node(@l,@t1,@t2)) -> c_7(append#(@l,append(flatten(@t1),flatten(@t2)))
                                                 ,append#(flatten(@t1),flatten(@t2))
                                                 ,flatten#(@t1)
                                                 ,flatten#(@t2))
             -->_4 flatten#(@t) -> c_5(flatten#1#(@t)):1
             -->_3 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
          3:S:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):7
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
          4:S:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys)):5
          
          5:S:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):6
          
          6:S:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):4
          
          7:S:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):8
          
          8:S:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):7
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):4
          
        Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified:
          flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
** Step 7.b:3: Decompose WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Decompose {onSelection = all cycle independent sub-graph, withBound = RelativeAdd}
    + Details:
        We analyse the complexity of following sub-problems (R) and (S).
        Problem (S) is obtained from the input problem by shifting strict rules from (R) into the weak component.
        
        Problem (R)
          - Strict DPs:
              flatten#(@t) -> c_5(flatten#1#(@t))
              flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
          - Weak DPs:
              flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
              insert#(@x,@l) -> c_9(insert#1#(@l,@x))
              insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
              insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
              insertionsort#(@l) -> c_14(insertionsort#1#(@l))
              insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          - Weak TRS:
              #cklt(#EQ()) -> #false()
              #cklt(#GT()) -> #false()
              #cklt(#LT()) -> #true()
              #compare(#0(),#0()) -> #EQ()
              #compare(#0(),#neg(@y)) -> #GT()
              #compare(#0(),#pos(@y)) -> #LT()
              #compare(#0(),#s(@y)) -> #LT()
              #compare(#neg(@x),#0()) -> #LT()
              #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
              #compare(#neg(@x),#pos(@y)) -> #LT()
              #compare(#pos(@x),#0()) -> #GT()
              #compare(#pos(@x),#neg(@y)) -> #GT()
              #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
              #compare(#s(@x),#0()) -> #GT()
              #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
              #less(@x,@y) -> #cklt(#compare(@x,@y))
              append(@l1,@l2) -> append#1(@l1,@l2)
              append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
              append#1(nil(),@l2) -> @l2
              flatten(@t) -> flatten#1(@t)
              flatten#1(leaf()) -> nil()
              flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
              insert(@x,@l) -> insert#1(@l,@x)
              insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
              insert#1(nil(),@x) -> ::(@x,nil())
              insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
              insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
              insertionsort(@l) -> insertionsort#1(@l)
              insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
              insertionsort#1(nil()) -> nil()
          - Signature:
              {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
              ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2
              ,flatten#/1,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1
              ,insertionsort#1#/1} / {#0/0,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0
              ,node/3,c_1/2,c_2/1,c_3/1,c_4/0,c_5/1,c_6/0,c_7/2,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2
              ,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0
              ,c_31/1}
          - Obligation:
              innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
              ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
              ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
        
        Problem (S)
          - Strict DPs:
              flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
              insert#(@x,@l) -> c_9(insert#1#(@l,@x))
              insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
              insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
              insertionsort#(@l) -> c_14(insertionsort#1#(@l))
              insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          - Weak DPs:
              flatten#(@t) -> c_5(flatten#1#(@t))
              flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
          - Weak TRS:
              #cklt(#EQ()) -> #false()
              #cklt(#GT()) -> #false()
              #cklt(#LT()) -> #true()
              #compare(#0(),#0()) -> #EQ()
              #compare(#0(),#neg(@y)) -> #GT()
              #compare(#0(),#pos(@y)) -> #LT()
              #compare(#0(),#s(@y)) -> #LT()
              #compare(#neg(@x),#0()) -> #LT()
              #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
              #compare(#neg(@x),#pos(@y)) -> #LT()
              #compare(#pos(@x),#0()) -> #GT()
              #compare(#pos(@x),#neg(@y)) -> #GT()
              #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
              #compare(#s(@x),#0()) -> #GT()
              #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
              #less(@x,@y) -> #cklt(#compare(@x,@y))
              append(@l1,@l2) -> append#1(@l1,@l2)
              append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
              append#1(nil(),@l2) -> @l2
              flatten(@t) -> flatten#1(@t)
              flatten#1(leaf()) -> nil()
              flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
              insert(@x,@l) -> insert#1(@l,@x)
              insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
              insert#1(nil(),@x) -> ::(@x,nil())
              insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
              insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
              insertionsort(@l) -> insertionsort#1(@l)
              insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
              insertionsort#1(nil()) -> nil()
          - Signature:
              {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
              ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2
              ,flatten#/1,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1
              ,insertionsort#1#/1} / {#0/0,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0
              ,node/3,c_1/2,c_2/1,c_3/1,c_4/0,c_5/1,c_6/0,c_7/2,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2
              ,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0
              ,c_31/1}
          - Obligation:
              innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
              ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
              ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
*** Step 7.b:3.a:1: RemoveWeakSuffixes WORST_CASE(?,O(n^1))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        RemoveWeakSuffixes
    + Details:
        Consider the dependency graph
          1:S:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2)):2
          
          2:S:flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):1
             -->_1 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
          3:W:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):1
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):7
          
          4:W:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys)):5
          
          5:W:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):6
          
          6:W:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):4
          
          7:W:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):8
          
          8:W:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):4
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):7
          
        The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed.
          7: insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          8: insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          4: insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          6: insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          5: insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
*** Step 7.b:3.a:2: SimplifyRHS WORST_CASE(?,O(n^1))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        SimplifyRHS
    + Details:
        Consider the dependency graph
          1:S:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2)):2
          
          2:S:flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):1
             -->_1 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
          3:W:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
        Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified:
          flattensort#(@t) -> c_8(flatten#(@t))
*** Step 7.b:3.a:3: UsableRules WORST_CASE(?,O(n^1))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
        - Weak DPs:
            flattensort#(@t) -> c_8(flatten#(@t))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        UsableRules
    + Details:
        We replace rewrite rules by usable rules:
          flatten#(@t) -> c_5(flatten#1#(@t))
          flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
          flattensort#(@t) -> c_8(flatten#(@t))
*** Step 7.b:3.a:4: PredecessorEstimationCP WORST_CASE(?,O(n^1))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
        - Weak DPs:
            flattensort#(@t) -> c_8(flatten#(@t))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        PredecessorEstimationCP {onSelectionCP = any intersect of rules of CDG leaf and strict-rules, withComplexityPair = NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing}}
    + Details:
        We first use the processor NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing} to orient following rules strictly:
          2: flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
          
        Consider the set of all dependency pairs
          1: flatten#(@t) -> c_5(flatten#1#(@t))
          2: flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
          3: flattensort#(@t) -> c_8(flatten#(@t))
        Processor NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing}induces the complexity certificateTIME (?,O(n^1))
        SPACE(?,?)on application of the dependency pairs
          {2}
        These cover all (indirect) predecessors of dependency pairs
          {1,2,3}
        their number of applications is equally bounded.
        The dependency pairs are shifted into the weak component.
**** Step 7.b:3.a:4.a:1: NaturalMI WORST_CASE(?,O(n^1))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
        - Weak DPs:
            flattensort#(@t) -> c_8(flatten#(@t))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Just first alternative for predecessorEstimation on any intersect of rules of CDG leaf and strict-rules}
    + Details:
        We apply a matrix interpretation of kind constructor based matrix interpretation:
        The following argument positions are considered usable:
          uargs(c_5) = {1},
          uargs(c_7) = {1,2},
          uargs(c_8) = {1}
        
        Following symbols are considered usable:
          {#cklt#,#compare#,#less#,append#,append#1#,flatten#,flatten#1#,flattensort#,insert#,insert#1#,insert#2#
          ,insertionsort#,insertionsort#1#}
        TcT has computed the following interpretation:
                        p(#0) = [0]                                    
                       p(#EQ) = [0]                                    
                       p(#GT) = [0]                                    
                       p(#LT) = [0]                                    
                     p(#cklt) = [0]                                    
                  p(#compare) = [0]                                    
                    p(#false) = [1]                                    
                     p(#less) = [0]                                    
                      p(#neg) = [1] x1 + [0]                           
                      p(#pos) = [1] x1 + [0]                           
                        p(#s) = [1] x1 + [0]                           
                     p(#true) = [0]                                    
                        p(::) = [1] x1 + [1] x2 + [0]                  
                    p(append) = [0]                                    
                  p(append#1) = [0]                                    
                   p(flatten) = [0]                                    
                 p(flatten#1) = [8]                                    
               p(flattensort) = [0]                                    
                    p(insert) = [1] x2 + [1]                           
                  p(insert#1) = [2] x1 + [1] x2 + [1]                  
                  p(insert#2) = [2] x1 + [1] x2 + [8] x3 + [1] x4 + [8]
             p(insertionsort) = [8] x1 + [1]                           
           p(insertionsort#1) = [4]                                    
                      p(leaf) = [0]                                    
                       p(nil) = [0]                                    
                      p(node) = [1] x1 + [1] x2 + [1] x3 + [9]         
                    p(#cklt#) = [0]                                    
                 p(#compare#) = [1] x1 + [0]                           
                    p(#less#) = [1] x2 + [1]                           
                   p(append#) = [1] x1 + [1]                           
                 p(append#1#) = [2] x2 + [8]                           
                  p(flatten#) = [2] x1 + [1]                           
                p(flatten#1#) = [2] x1 + [1]                           
              p(flattensort#) = [8] x1 + [1]                           
                   p(insert#) = [1]                                    
                 p(insert#1#) = [2] x1 + [1]                           
                 p(insert#2#) = [2] x1 + [1] x2 + [8] x3 + [1]         
            p(insertionsort#) = [8] x1 + [0]                           
          p(insertionsort#1#) = [8] x1 + [0]                           
                       p(c_1) = [1] x1 + [1]                           
                       p(c_2) = [2]                                    
                       p(c_3) = [1]                                    
                       p(c_4) = [8]                                    
                       p(c_5) = [1] x1 + [0]                           
                       p(c_6) = [1]                                    
                       p(c_7) = [1] x1 + [1] x2 + [8]                  
                       p(c_8) = [1] x1 + [0]                           
                       p(c_9) = [2]                                    
                      p(c_10) = [1] x1 + [1]                           
                      p(c_11) = [0]                                    
                      p(c_12) = [1]                                    
                      p(c_13) = [1]                                    
                      p(c_14) = [2]                                    
                      p(c_15) = [0]                                    
                      p(c_16) = [0]                                    
                      p(c_17) = [0]                                    
                      p(c_18) = [2]                                    
                      p(c_19) = [1]                                    
                      p(c_20) = [0]                                    
                      p(c_21) = [1]                                    
                      p(c_22) = [1]                                    
                      p(c_23) = [1]                                    
                      p(c_24) = [8]                                    
                      p(c_25) = [1]                                    
                      p(c_26) = [0]                                    
                      p(c_27) = [1]                                    
                      p(c_28) = [8]                                    
                      p(c_29) = [2] x1 + [8]                           
                      p(c_30) = [0]                                    
                      p(c_31) = [8]                                    
        
        Following rules are strictly oriented:
        flatten#1#(node(@l,@t1,@t2)) = [2] @l + [2] @t1 + [2] @t2 + [19]
                                     > [2] @t1 + [2] @t2 + [10]         
                                     = c_7(flatten#(@t1),flatten#(@t2)) 
        
        
        Following rules are (at-least) weakly oriented:
            flatten#(@t) =  [2] @t + [1]       
                         >= [2] @t + [1]       
                         =  c_5(flatten#1#(@t))
        
        flattensort#(@t) =  [8] @t + [1]       
                         >= [2] @t + [1]       
                         =  c_8(flatten#(@t))  
        
**** Step 7.b:3.a:4.a:2: Assumption WORST_CASE(?,O(1))
    + Considered Problem:
        - Strict DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
        - Weak DPs:
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
            flattensort#(@t) -> c_8(flatten#(@t))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Assumption {assumed = Certificate {spaceUB = Unknown, spaceLB = Unknown, timeUB = Poly (Just 0), timeLB = Unknown}}
    + Details:
        ()

**** Step 7.b:3.a:4.b:1: RemoveWeakSuffixes WORST_CASE(?,O(1))
    + Considered Problem:
        - Weak DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
            flattensort#(@t) -> c_8(flatten#(@t))
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        RemoveWeakSuffixes
    + Details:
        Consider the dependency graph
          1:W:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2)):2
          
          2:W:flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):1
             -->_1 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
          3:W:flattensort#(@t) -> c_8(flatten#(@t))
             -->_1 flatten#(@t) -> c_5(flatten#1#(@t)):1
          
        The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed.
          3: flattensort#(@t) -> c_8(flatten#(@t))
          1: flatten#(@t) -> c_5(flatten#1#(@t))
          2: flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
**** Step 7.b:3.a:4.b:2: EmptyProcessor WORST_CASE(?,O(1))
    + Considered Problem:
        
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        EmptyProcessor
    + Details:
        The problem is already closed. The intended complexity is O(1).

*** Step 7.b:3.b:1: RemoveWeakSuffixes WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak DPs:
            flatten#(@t) -> c_5(flatten#1#(@t))
            flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        RemoveWeakSuffixes
    + Details:
        Consider the dependency graph
          1:S:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):7
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):5
          
          2:S:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys)):3
          
          3:S:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):4
          
          4:S:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):2
          
          5:S:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):6
          
          6:S:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):5
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):2
          
          7:W:flatten#(@t) -> c_5(flatten#1#(@t))
             -->_1 flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2)):8
          
          8:W:flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
             -->_2 flatten#(@t) -> c_5(flatten#1#(@t)):7
             -->_1 flatten#(@t) -> c_5(flatten#1#(@t)):7
          
        The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed.
          7: flatten#(@t) -> c_5(flatten#1#(@t))
          8: flatten#1#(node(@l,@t1,@t2)) -> c_7(flatten#(@t1),flatten#(@t2))
*** Step 7.b:3.b:2: SimplifyRHS WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/2,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        SimplifyRHS
    + Details:
        Consider the dependency graph
          1:S:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)),flatten#(@t))
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):5
          
          2:S:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys)):3
          
          3:S:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):4
          
          4:S:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):2
          
          5:S:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):6
          
          6:S:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):5
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):2
          
        Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified:
          flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
*** Step 7.b:3.b:3: PredecessorEstimationCP WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        PredecessorEstimationCP {onSelectionCP = any intersect of rules of CDG leaf and strict-rules, withComplexityPair = NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing}}
    + Details:
        We first use the processor NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing} to orient following rules strictly:
          1: flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
          4: insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          
        The strictly oriented rules are moved into the weak component.
**** Step 7.b:3.b:3.a:1: NaturalPI WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Just first alternative for predecessorEstimation on any intersect of rules of CDG leaf and strict-rules}
    + Details:
        We apply a polynomial interpretation of kind constructor-based(mixed(2)):
        The following argument positions are considered usable:
          uargs(c_8) = {1},
          uargs(c_9) = {1},
          uargs(c_10) = {1},
          uargs(c_13) = {1},
          uargs(c_14) = {1},
          uargs(c_15) = {1,2}
        
        Following symbols are considered usable:
          {#cklt,#compare,#less,append,append#1,flatten,flatten#1,insert,insert#1,insert#2,insertionsort
          ,insertionsort#1,#cklt#,#compare#,#less#,append#,append#1#,flatten#,flatten#1#,flattensort#,insert#
          ,insert#1#,insert#2#,insertionsort#,insertionsort#1#}
        TcT has computed the following interpretation:
                        p(#0) = 1            
                       p(#EQ) = 0            
                       p(#GT) = 0            
                       p(#LT) = 1            
                     p(#cklt) = x1           
                  p(#compare) = x1*x2        
                    p(#false) = 0            
                     p(#less) = x1*x2        
                      p(#neg) = 1 + x1       
                      p(#pos) = 1 + x1       
                        p(#s) = 1 + x1       
                     p(#true) = 1            
                        p(::) = x1 + x2      
                    p(append) = x1 + x2      
                  p(append#1) = x1 + x2      
                   p(flatten) = x1           
                 p(flatten#1) = x1           
               p(flattensort) = 0            
                    p(insert) = x1 + x2      
                  p(insert#1) = x1 + x2      
                  p(insert#2) = x2 + x3 + x4 
             p(insertionsort) = x1           
           p(insertionsort#1) = x1           
                      p(leaf) = 0            
                       p(nil) = 0            
                      p(node) = x1 + x2 + x3 
                    p(#cklt#) = 0            
                 p(#compare#) = 0            
                    p(#less#) = 0            
                   p(append#) = 0            
                 p(append#1#) = 0            
                  p(flatten#) = 0            
                p(flatten#1#) = 0            
              p(flattensort#) = 1 + x1 + x1^2
                   p(insert#) = x1*x2        
                 p(insert#1#) = x1*x2        
                 p(insert#2#) = x1 + x2*x4   
            p(insertionsort#) = x1^2         
          p(insertionsort#1#) = x1^2         
                       p(c_1) = 0            
                       p(c_2) = 0            
                       p(c_3) = 0            
                       p(c_4) = 0            
                       p(c_5) = 0            
                       p(c_6) = 0            
                       p(c_7) = 0            
                       p(c_8) = x1           
                       p(c_9) = x1           
                      p(c_10) = x1           
                      p(c_11) = 0            
                      p(c_12) = 0            
                      p(c_13) = x1           
                      p(c_14) = x1           
                      p(c_15) = x1 + x2      
                      p(c_16) = 0            
                      p(c_17) = 0            
                      p(c_18) = 0            
                      p(c_19) = 0            
                      p(c_20) = 0            
                      p(c_21) = 0            
                      p(c_22) = 0            
                      p(c_23) = 0            
                      p(c_24) = 0            
                      p(c_25) = 0            
                      p(c_26) = 0            
                      p(c_27) = 0            
                      p(c_28) = 0            
                      p(c_29) = 0            
                      p(c_30) = 0            
                      p(c_31) = 0            
        
        Following rules are strictly oriented:
                    flattensort#(@t) = 1 + @t + @t^2                   
                                     > @t^2                            
                                     = c_8(insertionsort#(flatten(@t)))
        
        insert#2#(#true(),@x,@y,@ys) = 1 + @x*@ys                      
                                     > @x*@ys                          
                                     = c_13(insert#(@x,@ys))           
        
        
        Following rules are (at-least) weakly oriented:
                      insert#(@x,@l) =  @l*@x                                                   
                                     >= @l*@x                                                   
                                     =  c_9(insert#1#(@l,@x))                                   
        
            insert#1#(::(@y,@ys),@x) =  @x*@y + @x*@ys                                          
                                     >= @x*@y + @x*@ys                                          
                                     =  c_10(insert#2#(#less(@y,@x),@x,@y,@ys))                 
        
                  insertionsort#(@l) =  @l^2                                                    
                                     >= @l^2                                                    
                                     =  c_14(insertionsort#1#(@l))                              
        
        insertionsort#1#(::(@x,@xs)) =  2*@x*@xs + @x^2 + @xs^2                                 
                                     >= @x*@xs + @xs^2                                          
                                     =  c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        
                        #cklt(#EQ()) =  0                                                       
                                     >= 0                                                       
                                     =  #false()                                                
        
                        #cklt(#GT()) =  0                                                       
                                     >= 0                                                       
                                     =  #false()                                                
        
                        #cklt(#LT()) =  1                                                       
                                     >= 1                                                       
                                     =  #true()                                                 
        
                 #compare(#0(),#0()) =  1                                                       
                                     >= 0                                                       
                                     =  #EQ()                                                   
        
             #compare(#0(),#neg(@y)) =  1 + @y                                                  
                                     >= 0                                                       
                                     =  #GT()                                                   
        
             #compare(#0(),#pos(@y)) =  1 + @y                                                  
                                     >= 1                                                       
                                     =  #LT()                                                   
        
               #compare(#0(),#s(@y)) =  1 + @y                                                  
                                     >= 1                                                       
                                     =  #LT()                                                   
        
             #compare(#neg(@x),#0()) =  1 + @x                                                  
                                     >= 1                                                       
                                     =  #LT()                                                   
        
         #compare(#neg(@x),#neg(@y)) =  1 + @x + @x*@y + @y                                     
                                     >= @x*@y                                                   
                                     =  #compare(@y,@x)                                         
        
         #compare(#neg(@x),#pos(@y)) =  1 + @x + @x*@y + @y                                     
                                     >= 1                                                       
                                     =  #LT()                                                   
        
             #compare(#pos(@x),#0()) =  1 + @x                                                  
                                     >= 0                                                       
                                     =  #GT()                                                   
        
         #compare(#pos(@x),#neg(@y)) =  1 + @x + @x*@y + @y                                     
                                     >= 0                                                       
                                     =  #GT()                                                   
        
         #compare(#pos(@x),#pos(@y)) =  1 + @x + @x*@y + @y                                     
                                     >= @x*@y                                                   
                                     =  #compare(@x,@y)                                         
        
               #compare(#s(@x),#0()) =  1 + @x                                                  
                                     >= 0                                                       
                                     =  #GT()                                                   
        
             #compare(#s(@x),#s(@y)) =  1 + @x + @x*@y + @y                                     
                                     >= @x*@y                                                   
                                     =  #compare(@x,@y)                                         
        
                        #less(@x,@y) =  @x*@y                                                   
                                     >= @x*@y                                                   
                                     =  #cklt(#compare(@x,@y))                                  
        
                     append(@l1,@l2) =  @l1 + @l2                                               
                                     >= @l1 + @l2                                               
                                     =  append#1(@l1,@l2)                                       
        
            append#1(::(@x,@xs),@l2) =  @l2 + @x + @xs                                          
                                     >= @l2 + @x + @xs                                          
                                     =  ::(@x,append(@xs,@l2))                                  
        
                 append#1(nil(),@l2) =  @l2                                                     
                                     >= @l2                                                     
                                     =  @l2                                                     
        
                         flatten(@t) =  @t                                                      
                                     >= @t                                                      
                                     =  flatten#1(@t)                                           
        
                   flatten#1(leaf()) =  0                                                       
                                     >= 0                                                       
                                     =  nil()                                                   
        
         flatten#1(node(@l,@t1,@t2)) =  @l + @t1 + @t2                                          
                                     >= @l + @t1 + @t2                                          
                                     =  append(@l,append(flatten(@t1),flatten(@t2)))            
        
                       insert(@x,@l) =  @l + @x                                                 
                                     >= @l + @x                                                 
                                     =  insert#1(@l,@x)                                         
        
             insert#1(::(@y,@ys),@x) =  @x + @y + @ys                                           
                                     >= @x + @y + @ys                                           
                                     =  insert#2(#less(@y,@x),@x,@y,@ys)                        
        
                  insert#1(nil(),@x) =  @x                                                      
                                     >= @x                                                      
                                     =  ::(@x,nil())                                            
        
        insert#2(#false(),@x,@y,@ys) =  @x + @y + @ys                                           
                                     >= @x + @y + @ys                                           
                                     =  ::(@x,::(@y,@ys))                                       
        
         insert#2(#true(),@x,@y,@ys) =  @x + @y + @ys                                           
                                     >= @x + @y + @ys                                           
                                     =  ::(@y,insert(@x,@ys))                                   
        
                   insertionsort(@l) =  @l                                                      
                                     >= @l                                                      
                                     =  insertionsort#1(@l)                                     
        
         insertionsort#1(::(@x,@xs)) =  @x + @xs                                                
                                     >= @x + @xs                                                
                                     =  insert(@x,insertionsort(@xs))                           
        
              insertionsort#1(nil()) =  0                                                       
                                     >= 0                                                       
                                     =  nil()                                                   
        
**** Step 7.b:3.b:3.a:2: Assumption WORST_CASE(?,O(1))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Assumption {assumed = Certificate {spaceUB = Unknown, spaceLB = Unknown, timeUB = Poly (Just 0), timeLB = Unknown}}
    + Details:
        ()

**** Step 7.b:3.b:3.b:1: PredecessorEstimationCP WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        PredecessorEstimationCP {onSelectionCP = any intersect of rules of CDG leaf and strict-rules, withComplexityPair = NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing}}
    + Details:
        We first use the processor NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing} to orient following rules strictly:
          3: insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          
        Consider the set of all dependency pairs
          1: insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          2: insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
          3: insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          4: insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          5: flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
          6: insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
        Processor NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing}induces the complexity certificateTIME (?,O(n^1))
        SPACE(?,?)on application of the dependency pairs
          {3}
        These cover all (indirect) predecessors of dependency pairs
          {3,4,5}
        their number of applications is equally bounded.
        The dependency pairs are shifted into the weak component.
***** Step 7.b:3.b:3.b:1.a:1: NaturalMI WORST_CASE(?,O(n^1))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Just first alternative for predecessorEstimation on any intersect of rules of CDG leaf and strict-rules}
    + Details:
        We apply a matrix interpretation of kind constructor based matrix interpretation:
        The following argument positions are considered usable:
          uargs(c_8) = {1},
          uargs(c_9) = {1},
          uargs(c_10) = {1},
          uargs(c_13) = {1},
          uargs(c_14) = {1},
          uargs(c_15) = {1,2}
        
        Following symbols are considered usable:
          {append,append#1,flatten,flatten#1,#cklt#,#compare#,#less#,append#,append#1#,flatten#,flatten#1#
          ,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#}
        TcT has computed the following interpretation:
                        p(#0) = [1]                           
                       p(#EQ) = [0]                           
                       p(#GT) = [0]                           
                       p(#LT) = [0]                           
                     p(#cklt) = [1]                           
                  p(#compare) = [2] x1 + [4] x2 + [0]         
                    p(#false) = [0]                           
                     p(#less) = [2] x2 + [0]                  
                      p(#neg) = [2]                           
                      p(#pos) = [1] x1 + [0]                  
                        p(#s) = [0]                           
                     p(#true) = [0]                           
                        p(::) = [1] x2 + [4]                  
                    p(append) = [1] x1 + [1] x2 + [0]         
                  p(append#1) = [1] x1 + [1] x2 + [0]         
                   p(flatten) = [4] x1 + [0]                  
                 p(flatten#1) = [4] x1 + [0]                  
               p(flattensort) = [2] x1 + [1]                  
                    p(insert) = [4] x1 + [2]                  
                  p(insert#1) = [1] x2 + [0]                  
                  p(insert#2) = [1]                           
             p(insertionsort) = [0]                           
           p(insertionsort#1) = [0]                           
                      p(leaf) = [2]                           
                       p(nil) = [0]                           
                      p(node) = [1] x1 + [1] x2 + [1] x3 + [2]
                    p(#cklt#) = [0]                           
                 p(#compare#) = [1] x2 + [0]                  
                    p(#less#) = [1] x1 + [1]                  
                   p(append#) = [1] x1 + [0]                  
                 p(append#1#) = [2] x2 + [2]                  
                  p(flatten#) = [4] x1 + [0]                  
                p(flatten#1#) = [1] x1 + [0]                  
              p(flattensort#) = [4] x1 + [7]                  
                   p(insert#) = [0]                           
                 p(insert#1#) = [0]                           
                 p(insert#2#) = [0]                           
            p(insertionsort#) = [1] x1 + [6]                  
          p(insertionsort#1#) = [1] x1 + [4]                  
                       p(c_1) = [2]                           
                       p(c_2) = [0]                           
                       p(c_3) = [0]                           
                       p(c_4) = [0]                           
                       p(c_5) = [1]                           
                       p(c_6) = [0]                           
                       p(c_7) = [1] x1 + [1] x2 + [1]         
                       p(c_8) = [1] x1 + [1]                  
                       p(c_9) = [4] x1 + [0]                  
                      p(c_10) = [2] x1 + [0]                  
                      p(c_11) = [4]                           
                      p(c_12) = [0]                           
                      p(c_13) = [4] x1 + [0]                  
                      p(c_14) = [1] x1 + [1]                  
                      p(c_15) = [1] x1 + [1] x2 + [2]         
                      p(c_16) = [0]                           
                      p(c_17) = [1]                           
                      p(c_18) = [4]                           
                      p(c_19) = [0]                           
                      p(c_20) = [4]                           
                      p(c_21) = [0]                           
                      p(c_22) = [2]                           
                      p(c_23) = [0]                           
                      p(c_24) = [1]                           
                      p(c_25) = [4] x1 + [1]                  
                      p(c_26) = [2]                           
                      p(c_27) = [1]                           
                      p(c_28) = [1]                           
                      p(c_29) = [4] x1 + [1]                  
                      p(c_30) = [1]                           
                      p(c_31) = [1] x1 + [2]                  
        
        Following rules are strictly oriented:
        insertionsort#(@l) = [1] @l + [6]              
                           > [1] @l + [5]              
                           = c_14(insertionsort#1#(@l))
        
        
        Following rules are (at-least) weakly oriented:
                    flattensort#(@t) =  [4] @t + [7]                                            
                                     >= [4] @t + [7]                                            
                                     =  c_8(insertionsort#(flatten(@t)))                        
        
                      insert#(@x,@l) =  [0]                                                     
                                     >= [0]                                                     
                                     =  c_9(insert#1#(@l,@x))                                   
        
            insert#1#(::(@y,@ys),@x) =  [0]                                                     
                                     >= [0]                                                     
                                     =  c_10(insert#2#(#less(@y,@x),@x,@y,@ys))                 
        
        insert#2#(#true(),@x,@y,@ys) =  [0]                                                     
                                     >= [0]                                                     
                                     =  c_13(insert#(@x,@ys))                                   
        
        insertionsort#1#(::(@x,@xs)) =  [1] @xs + [8]                                           
                                     >= [1] @xs + [8]                                           
                                     =  c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        
                     append(@l1,@l2) =  [1] @l1 + [1] @l2 + [0]                                 
                                     >= [1] @l1 + [1] @l2 + [0]                                 
                                     =  append#1(@l1,@l2)                                       
        
            append#1(::(@x,@xs),@l2) =  [1] @l2 + [1] @xs + [4]                                 
                                     >= [1] @l2 + [1] @xs + [4]                                 
                                     =  ::(@x,append(@xs,@l2))                                  
        
                 append#1(nil(),@l2) =  [1] @l2 + [0]                                           
                                     >= [1] @l2 + [0]                                           
                                     =  @l2                                                     
        
                         flatten(@t) =  [4] @t + [0]                                            
                                     >= [4] @t + [0]                                            
                                     =  flatten#1(@t)                                           
        
                   flatten#1(leaf()) =  [8]                                                     
                                     >= [0]                                                     
                                     =  nil()                                                   
        
         flatten#1(node(@l,@t1,@t2)) =  [4] @l + [4] @t1 + [4] @t2 + [8]                        
                                     >= [1] @l + [4] @t1 + [4] @t2 + [0]                        
                                     =  append(@l,append(flatten(@t1),flatten(@t2)))            
        
***** Step 7.b:3.b:3.b:1.a:2: Assumption WORST_CASE(?,O(1))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Assumption {assumed = Certificate {spaceUB = Unknown, spaceLB = Unknown, timeUB = Poly (Just 0), timeLB = Unknown}}
    + Details:
        ()

***** Step 7.b:3.b:3.b:1.b:1: PredecessorEstimationCP WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        PredecessorEstimationCP {onSelectionCP = any intersect of rules of CDG leaf and strict-rules, withComplexityPair = NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing}}
    + Details:
        We first use the processor NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing} to orient following rules strictly:
          2: insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
          
        Consider the set of all dependency pairs
          1: insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          2: insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
          3: flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
          4: insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          5: insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          6: insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        Processor NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing}induces the complexity certificateTIME (?,O(n^2))
        SPACE(?,?)on application of the dependency pairs
          {2}
        These cover all (indirect) predecessors of dependency pairs
          {2,3,4}
        their number of applications is equally bounded.
        The dependency pairs are shifted into the weak component.
****** Step 7.b:3.b:3.b:1.b:1.a:1: NaturalPI WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Just first alternative for predecessorEstimation on any intersect of rules of CDG leaf and strict-rules}
    + Details:
        We apply a polynomial interpretation of kind constructor-based(mixed(2)):
        The following argument positions are considered usable:
          uargs(c_8) = {1},
          uargs(c_9) = {1},
          uargs(c_10) = {1},
          uargs(c_13) = {1},
          uargs(c_14) = {1},
          uargs(c_15) = {1,2}
        
        Following symbols are considered usable:
          {#cklt,#less,append,append#1,flatten,flatten#1,insert,insert#1,insert#2,insertionsort,insertionsort#1
          ,#cklt#,#compare#,#less#,append#,append#1#,flatten#,flatten#1#,flattensort#,insert#,insert#1#,insert#2#
          ,insertionsort#,insertionsort#1#}
        TcT has computed the following interpretation:
                        p(#0) = 0            
                       p(#EQ) = 0            
                       p(#GT) = 1            
                       p(#LT) = 0            
                     p(#cklt) = 1            
                  p(#compare) = x1           
                    p(#false) = 1            
                     p(#less) = 1            
                      p(#neg) = 0            
                      p(#pos) = 0            
                        p(#s) = x1           
                     p(#true) = 1            
                        p(::) = 1 + x2       
                    p(append) = x1 + x2      
                  p(append#1) = x1 + x2      
                   p(flatten) = x1           
                 p(flatten#1) = x1           
               p(flattensort) = 0            
                    p(insert) = 1 + x2       
                  p(insert#1) = 1 + x1       
                  p(insert#2) = 1 + x1^2 + x4
             p(insertionsort) = x1           
           p(insertionsort#1) = x1           
                      p(leaf) = 0            
                       p(nil) = 0            
                      p(node) = x1 + x2 + x3 
                    p(#cklt#) = 0            
                 p(#compare#) = 0            
                    p(#less#) = 0            
                   p(append#) = 0            
                 p(append#1#) = 0            
                  p(flatten#) = 0            
                p(flatten#1#) = 0            
              p(flattensort#) = x1^2         
                   p(insert#) = x2           
                 p(insert#1#) = x1           
                 p(insert#2#) = x4           
            p(insertionsort#) = x1^2         
          p(insertionsort#1#) = x1^2         
                       p(c_1) = 0            
                       p(c_2) = 0            
                       p(c_3) = 0            
                       p(c_4) = 0            
                       p(c_5) = 0            
                       p(c_6) = 0            
                       p(c_7) = 0            
                       p(c_8) = x1           
                       p(c_9) = x1           
                      p(c_10) = x1           
                      p(c_11) = 0            
                      p(c_12) = 0            
                      p(c_13) = x1           
                      p(c_14) = x1           
                      p(c_15) = 1 + x1 + x2  
                      p(c_16) = 0            
                      p(c_17) = 0            
                      p(c_18) = 0            
                      p(c_19) = 0            
                      p(c_20) = 0            
                      p(c_21) = 0            
                      p(c_22) = 0            
                      p(c_23) = 0            
                      p(c_24) = 0            
                      p(c_25) = 0            
                      p(c_26) = 0            
                      p(c_27) = 0            
                      p(c_28) = 0            
                      p(c_29) = 0            
                      p(c_30) = 0            
                      p(c_31) = 0            
        
        Following rules are strictly oriented:
        insert#1#(::(@y,@ys),@x) = 1 + @ys                                
                                 > @ys                                    
                                 = c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
        
        
        Following rules are (at-least) weakly oriented:
                    flattensort#(@t) =  @t^2                                                    
                                     >= @t^2                                                    
                                     =  c_8(insertionsort#(flatten(@t)))                        
        
                      insert#(@x,@l) =  @l                                                      
                                     >= @l                                                      
                                     =  c_9(insert#1#(@l,@x))                                   
        
        insert#2#(#true(),@x,@y,@ys) =  @ys                                                     
                                     >= @ys                                                     
                                     =  c_13(insert#(@x,@ys))                                   
        
                  insertionsort#(@l) =  @l^2                                                    
                                     >= @l^2                                                    
                                     =  c_14(insertionsort#1#(@l))                              
        
        insertionsort#1#(::(@x,@xs)) =  1 + 2*@xs + @xs^2                                       
                                     >= 1 + @xs + @xs^2                                         
                                     =  c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        
                        #cklt(#EQ()) =  1                                                       
                                     >= 1                                                       
                                     =  #false()                                                
        
                        #cklt(#GT()) =  1                                                       
                                     >= 1                                                       
                                     =  #false()                                                
        
                        #cklt(#LT()) =  1                                                       
                                     >= 1                                                       
                                     =  #true()                                                 
        
                        #less(@x,@y) =  1                                                       
                                     >= 1                                                       
                                     =  #cklt(#compare(@x,@y))                                  
        
                     append(@l1,@l2) =  @l1 + @l2                                               
                                     >= @l1 + @l2                                               
                                     =  append#1(@l1,@l2)                                       
        
            append#1(::(@x,@xs),@l2) =  1 + @l2 + @xs                                           
                                     >= 1 + @l2 + @xs                                           
                                     =  ::(@x,append(@xs,@l2))                                  
        
                 append#1(nil(),@l2) =  @l2                                                     
                                     >= @l2                                                     
                                     =  @l2                                                     
        
                         flatten(@t) =  @t                                                      
                                     >= @t                                                      
                                     =  flatten#1(@t)                                           
        
                   flatten#1(leaf()) =  0                                                       
                                     >= 0                                                       
                                     =  nil()                                                   
        
         flatten#1(node(@l,@t1,@t2)) =  @l + @t1 + @t2                                          
                                     >= @l + @t1 + @t2                                          
                                     =  append(@l,append(flatten(@t1),flatten(@t2)))            
        
                       insert(@x,@l) =  1 + @l                                                  
                                     >= 1 + @l                                                  
                                     =  insert#1(@l,@x)                                         
        
             insert#1(::(@y,@ys),@x) =  2 + @ys                                                 
                                     >= 2 + @ys                                                 
                                     =  insert#2(#less(@y,@x),@x,@y,@ys)                        
        
                  insert#1(nil(),@x) =  1                                                       
                                     >= 1                                                       
                                     =  ::(@x,nil())                                            
        
        insert#2(#false(),@x,@y,@ys) =  2 + @ys                                                 
                                     >= 2 + @ys                                                 
                                     =  ::(@x,::(@y,@ys))                                       
        
         insert#2(#true(),@x,@y,@ys) =  2 + @ys                                                 
                                     >= 2 + @ys                                                 
                                     =  ::(@y,insert(@x,@ys))                                   
        
                   insertionsort(@l) =  @l                                                      
                                     >= @l                                                      
                                     =  insertionsort#1(@l)                                     
        
         insertionsort#1(::(@x,@xs)) =  1 + @xs                                                 
                                     >= 1 + @xs                                                 
                                     =  insert(@x,insertionsort(@xs))                           
        
              insertionsort#1(nil()) =  0                                                       
                                     >= 0                                                       
                                     =  nil()                                                   
        
****** Step 7.b:3.b:3.b:1.b:1.a:2: Assumption WORST_CASE(?,O(1))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Assumption {assumed = Certificate {spaceUB = Unknown, spaceLB = Unknown, timeUB = Poly (Just 0), timeLB = Unknown}}
    + Details:
        ()

****** Step 7.b:3.b:3.b:1.b:1.b:1: PredecessorEstimationCP WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        PredecessorEstimationCP {onSelectionCP = any intersect of rules of CDG leaf and strict-rules, withComplexityPair = NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing}}
    + Details:
        We first use the processor NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing} to orient following rules strictly:
          1: insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          
        Consider the set of all dependency pairs
          1: insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          2: flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
          3: insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
          4: insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          5: insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          6: insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        Processor NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing}induces the complexity certificateTIME (?,O(n^2))
        SPACE(?,?)on application of the dependency pairs
          {1}
        These cover all (indirect) predecessors of dependency pairs
          {1,2,3,4}
        their number of applications is equally bounded.
        The dependency pairs are shifted into the weak component.
******* Step 7.b:3.b:3.b:1.b:1.b:1.a:1: NaturalPI WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict DPs:
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Just first alternative for predecessorEstimation on any intersect of rules of CDG leaf and strict-rules}
    + Details:
        We apply a polynomial interpretation of kind constructor-based(mixed(2)):
        The following argument positions are considered usable:
          uargs(c_8) = {1},
          uargs(c_9) = {1},
          uargs(c_10) = {1},
          uargs(c_13) = {1},
          uargs(c_14) = {1},
          uargs(c_15) = {1,2}
        
        Following symbols are considered usable:
          {#cklt,#less,append,append#1,flatten,flatten#1,insert,insert#1,insert#2,insertionsort,insertionsort#1
          ,#cklt#,#compare#,#less#,append#,append#1#,flatten#,flatten#1#,flattensort#,insert#,insert#1#,insert#2#
          ,insertionsort#,insertionsort#1#}
        TcT has computed the following interpretation:
                        p(#0) = 0               
                       p(#EQ) = 1               
                       p(#GT) = 0               
                       p(#LT) = 1               
                     p(#cklt) = 1               
                  p(#compare) = 0               
                    p(#false) = 1               
                     p(#less) = 1               
                      p(#neg) = 0               
                      p(#pos) = 0               
                        p(#s) = 0               
                     p(#true) = 1               
                        p(::) = 1 + x2          
                    p(append) = x1 + x2         
                  p(append#1) = x1 + x2         
                   p(flatten) = x1              
                 p(flatten#1) = x1              
               p(flattensort) = 0               
                    p(insert) = 1 + x2          
                  p(insert#1) = 1 + x1          
                  p(insert#2) = 1 + x1*x4 + x1^2
             p(insertionsort) = x1              
           p(insertionsort#1) = x1              
                      p(leaf) = 0               
                       p(nil) = 0               
                      p(node) = x1 + x2 + x3    
                    p(#cklt#) = 0               
                 p(#compare#) = 0               
                    p(#less#) = 0               
                   p(append#) = 0               
                 p(append#1#) = 0               
                  p(flatten#) = 0               
                p(flatten#1#) = 0               
              p(flattensort#) = x1^2            
                   p(insert#) = 1 + x2          
                 p(insert#1#) = x1              
                 p(insert#2#) = 1 + x4          
            p(insertionsort#) = x1^2            
          p(insertionsort#1#) = x1^2            
                       p(c_1) = 0               
                       p(c_2) = 0               
                       p(c_3) = 0               
                       p(c_4) = 0               
                       p(c_5) = 0               
                       p(c_6) = 0               
                       p(c_7) = 0               
                       p(c_8) = x1              
                       p(c_9) = x1              
                      p(c_10) = x1              
                      p(c_11) = 0               
                      p(c_12) = 0               
                      p(c_13) = x1              
                      p(c_14) = x1              
                      p(c_15) = x1 + x2         
                      p(c_16) = 0               
                      p(c_17) = 0               
                      p(c_18) = 0               
                      p(c_19) = 0               
                      p(c_20) = 0               
                      p(c_21) = 0               
                      p(c_22) = 0               
                      p(c_23) = 0               
                      p(c_24) = 0               
                      p(c_25) = 0               
                      p(c_26) = 0               
                      p(c_27) = 0               
                      p(c_28) = 0               
                      p(c_29) = 0               
                      p(c_30) = 0               
                      p(c_31) = 0               
        
        Following rules are strictly oriented:
        insert#(@x,@l) = 1 + @l               
                       > @l                   
                       = c_9(insert#1#(@l,@x))
        
        
        Following rules are (at-least) weakly oriented:
                    flattensort#(@t) =  @t^2                                                    
                                     >= @t^2                                                    
                                     =  c_8(insertionsort#(flatten(@t)))                        
        
            insert#1#(::(@y,@ys),@x) =  1 + @ys                                                 
                                     >= 1 + @ys                                                 
                                     =  c_10(insert#2#(#less(@y,@x),@x,@y,@ys))                 
        
        insert#2#(#true(),@x,@y,@ys) =  1 + @ys                                                 
                                     >= 1 + @ys                                                 
                                     =  c_13(insert#(@x,@ys))                                   
        
                  insertionsort#(@l) =  @l^2                                                    
                                     >= @l^2                                                    
                                     =  c_14(insertionsort#1#(@l))                              
        
        insertionsort#1#(::(@x,@xs)) =  1 + 2*@xs + @xs^2                                       
                                     >= 1 + @xs + @xs^2                                         
                                     =  c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        
                        #cklt(#EQ()) =  1                                                       
                                     >= 1                                                       
                                     =  #false()                                                
        
                        #cklt(#GT()) =  1                                                       
                                     >= 1                                                       
                                     =  #false()                                                
        
                        #cklt(#LT()) =  1                                                       
                                     >= 1                                                       
                                     =  #true()                                                 
        
                        #less(@x,@y) =  1                                                       
                                     >= 1                                                       
                                     =  #cklt(#compare(@x,@y))                                  
        
                     append(@l1,@l2) =  @l1 + @l2                                               
                                     >= @l1 + @l2                                               
                                     =  append#1(@l1,@l2)                                       
        
            append#1(::(@x,@xs),@l2) =  1 + @l2 + @xs                                           
                                     >= 1 + @l2 + @xs                                           
                                     =  ::(@x,append(@xs,@l2))                                  
        
                 append#1(nil(),@l2) =  @l2                                                     
                                     >= @l2                                                     
                                     =  @l2                                                     
        
                         flatten(@t) =  @t                                                      
                                     >= @t                                                      
                                     =  flatten#1(@t)                                           
        
                   flatten#1(leaf()) =  0                                                       
                                     >= 0                                                       
                                     =  nil()                                                   
        
         flatten#1(node(@l,@t1,@t2)) =  @l + @t1 + @t2                                          
                                     >= @l + @t1 + @t2                                          
                                     =  append(@l,append(flatten(@t1),flatten(@t2)))            
        
                       insert(@x,@l) =  1 + @l                                                  
                                     >= 1 + @l                                                  
                                     =  insert#1(@l,@x)                                         
        
             insert#1(::(@y,@ys),@x) =  2 + @ys                                                 
                                     >= 2 + @ys                                                 
                                     =  insert#2(#less(@y,@x),@x,@y,@ys)                        
        
                  insert#1(nil(),@x) =  1                                                       
                                     >= 1                                                       
                                     =  ::(@x,nil())                                            
        
        insert#2(#false(),@x,@y,@ys) =  2 + @ys                                                 
                                     >= 2 + @ys                                                 
                                     =  ::(@x,::(@y,@ys))                                       
        
         insert#2(#true(),@x,@y,@ys) =  2 + @ys                                                 
                                     >= 2 + @ys                                                 
                                     =  ::(@y,insert(@x,@ys))                                   
        
                   insertionsort(@l) =  @l                                                      
                                     >= @l                                                      
                                     =  insertionsort#1(@l)                                     
        
         insertionsort#1(::(@x,@xs)) =  1 + @xs                                                 
                                     >= 1 + @xs                                                 
                                     =  insert(@x,insertionsort(@xs))                           
        
              insertionsort#1(nil()) =  0                                                       
                                     >= 0                                                       
                                     =  nil()                                                   
        
******* Step 7.b:3.b:3.b:1.b:1.b:1.a:2: Assumption WORST_CASE(?,O(1))
    + Considered Problem:
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        Assumption {assumed = Certificate {spaceUB = Unknown, spaceLB = Unknown, timeUB = Poly (Just 0), timeLB = Unknown}}
    + Details:
        ()

******* Step 7.b:3.b:3.b:1.b:1.b:1.b:1: RemoveWeakSuffixes WORST_CASE(?,O(1))
    + Considered Problem:
        - Weak DPs:
            flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
            insert#(@x,@l) -> c_9(insert#1#(@l,@x))
            insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
            insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
            insertionsort#(@l) -> c_14(insertionsort#1#(@l))
            insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        RemoveWeakSuffixes
    + Details:
        Consider the dependency graph
          1:W:flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
             -->_1 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):5
          
          2:W:insert#(@x,@l) -> c_9(insert#1#(@l,@x))
             -->_1 insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys)):3
          
          3:W:insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
             -->_1 insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys)):4
          
          4:W:insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):2
          
          5:W:insertionsort#(@l) -> c_14(insertionsort#1#(@l))
             -->_1 insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs)):6
          
          6:W:insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
             -->_2 insertionsort#(@l) -> c_14(insertionsort#1#(@l)):5
             -->_1 insert#(@x,@l) -> c_9(insert#1#(@l,@x)):2
          
        The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed.
          1: flattensort#(@t) -> c_8(insertionsort#(flatten(@t)))
          5: insertionsort#(@l) -> c_14(insertionsort#1#(@l))
          6: insertionsort#1#(::(@x,@xs)) -> c_15(insert#(@x,insertionsort(@xs)),insertionsort#(@xs))
          2: insert#(@x,@l) -> c_9(insert#1#(@l,@x))
          4: insert#2#(#true(),@x,@y,@ys) -> c_13(insert#(@x,@ys))
          3: insert#1#(::(@y,@ys),@x) -> c_10(insert#2#(#less(@y,@x),@x,@y,@ys))
******* Step 7.b:3.b:3.b:1.b:1.b:1.b:2: EmptyProcessor WORST_CASE(?,O(1))
    + Considered Problem:
        - Weak TRS:
            #cklt(#EQ()) -> #false()
            #cklt(#GT()) -> #false()
            #cklt(#LT()) -> #true()
            #compare(#0(),#0()) -> #EQ()
            #compare(#0(),#neg(@y)) -> #GT()
            #compare(#0(),#pos(@y)) -> #LT()
            #compare(#0(),#s(@y)) -> #LT()
            #compare(#neg(@x),#0()) -> #LT()
            #compare(#neg(@x),#neg(@y)) -> #compare(@y,@x)
            #compare(#neg(@x),#pos(@y)) -> #LT()
            #compare(#pos(@x),#0()) -> #GT()
            #compare(#pos(@x),#neg(@y)) -> #GT()
            #compare(#pos(@x),#pos(@y)) -> #compare(@x,@y)
            #compare(#s(@x),#0()) -> #GT()
            #compare(#s(@x),#s(@y)) -> #compare(@x,@y)
            #less(@x,@y) -> #cklt(#compare(@x,@y))
            append(@l1,@l2) -> append#1(@l1,@l2)
            append#1(::(@x,@xs),@l2) -> ::(@x,append(@xs,@l2))
            append#1(nil(),@l2) -> @l2
            flatten(@t) -> flatten#1(@t)
            flatten#1(leaf()) -> nil()
            flatten#1(node(@l,@t1,@t2)) -> append(@l,append(flatten(@t1),flatten(@t2)))
            insert(@x,@l) -> insert#1(@l,@x)
            insert#1(::(@y,@ys),@x) -> insert#2(#less(@y,@x),@x,@y,@ys)
            insert#1(nil(),@x) -> ::(@x,nil())
            insert#2(#false(),@x,@y,@ys) -> ::(@x,::(@y,@ys))
            insert#2(#true(),@x,@y,@ys) -> ::(@y,insert(@x,@ys))
            insertionsort(@l) -> insertionsort#1(@l)
            insertionsort#1(::(@x,@xs)) -> insert(@x,insertionsort(@xs))
            insertionsort#1(nil()) -> nil()
        - Signature:
            {#cklt/1,#compare/2,#less/2,append/2,append#1/2,flatten/1,flatten#1/1,flattensort/1,insert/2,insert#1/2
            ,insert#2/4,insertionsort/1,insertionsort#1/1,#cklt#/1,#compare#/2,#less#/2,append#/2,append#1#/2,flatten#/1
            ,flatten#1#/1,flattensort#/1,insert#/2,insert#1#/2,insert#2#/4,insertionsort#/1,insertionsort#1#/1} / {#0/0
            ,#EQ/0,#GT/0,#LT/0,#false/0,#neg/1,#pos/1,#s/1,#true/0,::/2,leaf/0,nil/0,node/3,c_1/2,c_2/1,c_3/1,c_4/0
            ,c_5/1,c_6/0,c_7/2,c_8/1,c_9/1,c_10/1,c_11/0,c_12/0,c_13/1,c_14/1,c_15/2,c_16/0,c_17/0,c_18/0,c_19/0,c_20/0
            ,c_21/0,c_22/0,c_23/0,c_24/0,c_25/1,c_26/0,c_27/0,c_28/0,c_29/1,c_30/0,c_31/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {#cklt#,#compare#,#less#,append#,append#1#,flatten#
            ,flatten#1#,flattensort#,insert#,insert#1#,insert#2#,insertionsort#,insertionsort#1#} and constructors {#0
            ,#EQ,#GT,#LT,#false,#neg,#pos,#s,#true,::,leaf,nil,node}
    + Applied Processor:
        EmptyProcessor
    + Details:
        The problem is already closed. The intended complexity is O(1).

WORST_CASE(?,O(n^2))