We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^2)).

Strict Trs:
  { from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , first(X1, X2) -> n__first(X1, X2)
  , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
  , first(0(), Z) -> nil()
  , activate(X) -> X
  , activate(n__from(X)) -> from(X)
  , activate(n__first(X1, X2)) -> first(X1, X2)
  , sel(s(X), cons(Y, Z)) -> sel(X, activate(Z))
  , sel(0(), cons(X, Z)) -> X }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^2))

We add the following weak dependency pairs:

Strict DPs:
  { from^#(X) -> c_1()
  , from^#(X) -> c_2()
  , first^#(X1, X2) -> c_3()
  , first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
  , first^#(0(), Z) -> c_5()
  , activate^#(X) -> c_6()
  , activate^#(n__from(X)) -> c_7(from^#(X))
  , activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
  , sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z)))
  , sel^#(0(), cons(X, Z)) -> c_10() }

and mark the set of starting terms.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^2)).

Strict DPs:
  { from^#(X) -> c_1()
  , from^#(X) -> c_2()
  , first^#(X1, X2) -> c_3()
  , first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
  , first^#(0(), Z) -> c_5()
  , activate^#(X) -> c_6()
  , activate^#(n__from(X)) -> c_7(from^#(X))
  , activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
  , sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z)))
  , sel^#(0(), cons(X, Z)) -> c_10() }
Strict Trs:
  { from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , first(X1, X2) -> n__first(X1, X2)
  , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
  , first(0(), Z) -> nil()
  , activate(X) -> X
  , activate(n__from(X)) -> from(X)
  , activate(n__first(X1, X2)) -> first(X1, X2)
  , sel(s(X), cons(Y, Z)) -> sel(X, activate(Z))
  , sel(0(), cons(X, Z)) -> X }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^2))

We replace rewrite rules by usable rules:

  Strict Usable Rules:
    { from(X) -> cons(X, n__from(s(X)))
    , from(X) -> n__from(X)
    , first(X1, X2) -> n__first(X1, X2)
    , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
    , first(0(), Z) -> nil()
    , activate(X) -> X
    , activate(n__from(X)) -> from(X)
    , activate(n__first(X1, X2)) -> first(X1, X2) }

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^2)).

Strict DPs:
  { from^#(X) -> c_1()
  , from^#(X) -> c_2()
  , first^#(X1, X2) -> c_3()
  , first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
  , first^#(0(), Z) -> c_5()
  , activate^#(X) -> c_6()
  , activate^#(n__from(X)) -> c_7(from^#(X))
  , activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
  , sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z)))
  , sel^#(0(), cons(X, Z)) -> c_10() }
Strict Trs:
  { from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , first(X1, X2) -> n__first(X1, X2)
  , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
  , first(0(), Z) -> nil()
  , activate(X) -> X
  , activate(n__from(X)) -> from(X)
  , activate(n__first(X1, X2)) -> first(X1, X2) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^2))

The weightgap principle applies (using the following constant
growth matrix-interpretation)

The following argument positions are usable:
  Uargs(cons) = {2}, Uargs(n__first) = {2}, Uargs(c_4) = {1},
  Uargs(c_7) = {1}, Uargs(c_8) = {1}, Uargs(sel^#) = {2},
  Uargs(c_9) = {1}

TcT has computed the following constructor-restricted matrix
interpretation.

          [from](x1) = [2]                      
                       [2]                      
                                                
      [cons](x1, x2) = [1 1] x2 + [0]           
                       [0 1]      [0]           
                                                
       [n__from](x1) = [0]                      
                       [1]                      
                                                
             [s](x1) = [1 1] x1 + [2]           
                       [0 0]      [2]           
                                                
     [first](x1, x2) = [1 1] x1 + [1 0] x2 + [1]
                       [0 0]      [0 0]      [2]
                                                
                 [0] = [0]                      
                       [0]                      
                                                
               [nil] = [0]                      
                       [0]                      
                                                
  [n__first](x1, x2) = [1 1] x1 + [1 0] x2 + [0]
                       [0 0]      [0 0]      [2]
                                                
      [activate](x1) = [1 1] x1 + [2]           
                       [0 1]      [1]           
                                                
        [from^#](x1) = [1]                      
                       [0]                      
                                                
               [c_1] = [0]                      
                       [0]                      
                                                
               [c_2] = [0]                      
                       [0]                      
                                                
   [first^#](x1, x2) = [0]                      
                       [0]                      
                                                
               [c_3] = [0]                      
                       [0]                      
                                                
           [c_4](x1) = [1 0] x1 + [0]           
                       [0 1]      [0]           
                                                
    [activate^#](x1) = [0]                      
                       [0]                      
                                                
               [c_5] = [0]                      
                       [0]                      
                                                
               [c_6] = [0]                      
                       [0]                      
                                                
           [c_7](x1) = [1 0] x1 + [1]           
                       [0 1]      [0]           
                                                
           [c_8](x1) = [1 0] x1 + [0]           
                       [0 1]      [0]           
                                                
     [sel^#](x1, x2) = [2 2] x2 + [0]           
                       [0 0]      [0]           
                                                
           [c_9](x1) = [1 0] x1 + [0]           
                       [0 1]      [0]           
                                                
              [c_10] = [0]                      
                       [0]                      

The order satisfies the following ordering constraints:

                       [from(X)] =  [2]                                
                                    [2]                                
                                 >  [1]                                
                                    [1]                                
                                 =  [cons(X, n__from(s(X)))]           
                                                                       
                       [from(X)] =  [2]                                
                                    [2]                                
                                 >  [0]                                
                                    [1]                                
                                 =  [n__from(X)]                       
                                                                       
                 [first(X1, X2)] =  [1 1] X1 + [1 0] X2 + [1]          
                                    [0 0]      [0 0]      [2]          
                                 >  [1 1] X1 + [1 0] X2 + [0]          
                                    [0 0]      [0 0]      [2]          
                                 =  [n__first(X1, X2)]                 
                                                                       
       [first(s(X), cons(Y, Z))] =  [1 1] X + [1 1] Z + [5]            
                                    [0 0]     [0 0]     [2]            
                                 >  [1 1] X + [1 1] Z + [4]            
                                    [0 0]     [0 0]     [2]            
                                 =  [cons(Y, n__first(X, activate(Z)))]
                                                                       
                 [first(0(), Z)] =  [1 0] Z + [1]                      
                                    [0 0]     [2]                      
                                 >  [0]                                
                                    [0]                                
                                 =  [nil()]                            
                                                                       
                   [activate(X)] =  [1 1] X + [2]                      
                                    [0 1]     [1]                      
                                 >  [1 0] X + [0]                      
                                    [0 1]     [0]                      
                                 =  [X]                                
                                                                       
          [activate(n__from(X))] =  [3]                                
                                    [2]                                
                                 >  [2]                                
                                    [2]                                
                                 =  [from(X)]                          
                                                                       
    [activate(n__first(X1, X2))] =  [1 1] X1 + [1 0] X2 + [4]          
                                    [0 0]      [0 0]      [3]          
                                 >  [1 1] X1 + [1 0] X2 + [1]          
                                    [0 0]      [0 0]      [2]          
                                 =  [first(X1, X2)]                    
                                                                       
                     [from^#(X)] =  [1]                                
                                    [0]                                
                                 >  [0]                                
                                    [0]                                
                                 =  [c_1()]                            
                                                                       
                     [from^#(X)] =  [1]                                
                                    [0]                                
                                 >  [0]                                
                                    [0]                                
                                 =  [c_2()]                            
                                                                       
               [first^#(X1, X2)] =  [0]                                
                                    [0]                                
                                 >= [0]                                
                                    [0]                                
                                 =  [c_3()]                            
                                                                       
     [first^#(s(X), cons(Y, Z))] =  [0]                                
                                    [0]                                
                                 >= [0]                                
                                    [0]                                
                                 =  [c_4(activate^#(Z))]               
                                                                       
               [first^#(0(), Z)] =  [0]                                
                                    [0]                                
                                 >= [0]                                
                                    [0]                                
                                 =  [c_5()]                            
                                                                       
                 [activate^#(X)] =  [0]                                
                                    [0]                                
                                 >= [0]                                
                                    [0]                                
                                 =  [c_6()]                            
                                                                       
        [activate^#(n__from(X))] =  [0]                                
                                    [0]                                
                                 ?  [2]                                
                                    [0]                                
                                 =  [c_7(from^#(X))]                   
                                                                       
  [activate^#(n__first(X1, X2))] =  [0]                                
                                    [0]                                
                                 >= [0]                                
                                    [0]                                
                                 =  [c_8(first^#(X1, X2))]             
                                                                       
       [sel^#(s(X), cons(Y, Z))] =  [2 4] Z + [0]                      
                                    [0 0]     [0]                      
                                 ?  [2 4] Z + [6]                      
                                    [0 0]     [0]                      
                                 =  [c_9(sel^#(X, activate(Z)))]       
                                                                       
        [sel^#(0(), cons(X, Z))] =  [2 4] Z + [0]                      
                                    [0 0]     [0]                      
                                 >= [0]                                
                                    [0]                                
                                 =  [c_10()]                           
                                                                       

Further, it can be verified that all rules not oriented are covered by the weightgap condition.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict DPs:
  { first^#(X1, X2) -> c_3()
  , first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
  , first^#(0(), Z) -> c_5()
  , activate^#(X) -> c_6()
  , activate^#(n__from(X)) -> c_7(from^#(X))
  , activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
  , sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z)))
  , sel^#(0(), cons(X, Z)) -> c_10() }
Weak DPs:
  { from^#(X) -> c_1()
  , from^#(X) -> c_2() }
Weak Trs:
  { from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , first(X1, X2) -> n__first(X1, X2)
  , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
  , first(0(), Z) -> nil()
  , activate(X) -> X
  , activate(n__from(X)) -> from(X)
  , activate(n__first(X1, X2)) -> first(X1, X2) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

We estimate the number of application of {1,3,4,5,8} by
applications of Pre({1,3,4,5,8}) = {2,6,7}. Here rules are labeled
as follows:

  DPs:
    { 1: first^#(X1, X2) -> c_3()
    , 2: first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
    , 3: first^#(0(), Z) -> c_5()
    , 4: activate^#(X) -> c_6()
    , 5: activate^#(n__from(X)) -> c_7(from^#(X))
    , 6: activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
    , 7: sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z)))
    , 8: sel^#(0(), cons(X, Z)) -> c_10()
    , 9: from^#(X) -> c_1()
    , 10: from^#(X) -> c_2() }

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict DPs:
  { first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
  , activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
  , sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z))) }
Weak DPs:
  { from^#(X) -> c_1()
  , from^#(X) -> c_2()
  , first^#(X1, X2) -> c_3()
  , first^#(0(), Z) -> c_5()
  , activate^#(X) -> c_6()
  , activate^#(n__from(X)) -> c_7(from^#(X))
  , sel^#(0(), cons(X, Z)) -> c_10() }
Weak Trs:
  { from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , first(X1, X2) -> n__first(X1, X2)
  , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
  , first(0(), Z) -> nil()
  , activate(X) -> X
  , activate(n__from(X)) -> from(X)
  , activate(n__first(X1, X2)) -> first(X1, X2) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

The following weak DPs constitute a sub-graph of the DG that is
closed under successors. The DPs are removed.

{ from^#(X) -> c_1()
, from^#(X) -> c_2()
, first^#(X1, X2) -> c_3()
, first^#(0(), Z) -> c_5()
, activate^#(X) -> c_6()
, activate^#(n__from(X)) -> c_7(from^#(X))
, sel^#(0(), cons(X, Z)) -> c_10() }

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict DPs:
  { first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
  , activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
  , sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z))) }
Weak Trs:
  { from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , first(X1, X2) -> n__first(X1, X2)
  , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
  , first(0(), Z) -> nil()
  , activate(X) -> X
  , activate(n__from(X)) -> from(X)
  , activate(n__first(X1, X2)) -> first(X1, X2) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

We use the processor 'Small Polynomial Path Order (PS,1-bounded)'
to orient following rules strictly.

DPs:
  { 1: first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
  , 2: activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
  , 3: sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z))) }

Sub-proof:
----------
  The input was oriented with the instance of 'Small Polynomial Path
  Order (PS,1-bounded)' as induced by the safe mapping
  
   safe(from) = {1}, safe(cons) = {1, 2}, safe(n__from) = {1},
   safe(s) = {1}, safe(first) = {}, safe(0) = {}, safe(nil) = {},
   safe(n__first) = {1, 2}, safe(activate) = {}, safe(first^#) = {1},
   safe(c_4) = {}, safe(activate^#) = {}, safe(c_8) = {},
   safe(sel^#) = {2}, safe(c_9) = {}
  
  and precedence
  
   first > activate, sel^# > activate, first^# ~ activate^# .
  
  Following symbols are considered recursive:
  
   {first^#, activate^#, sel^#}
  
  The recursion depth is 1.
  
  Further, following argument filtering is employed:
  
   pi(from) = [1], pi(cons) = [2], pi(n__from) = 1, pi(s) = [1],
   pi(first) = [], pi(0) = [], pi(nil) = [], pi(n__first) = [2],
   pi(activate) = [1], pi(first^#) = [2], pi(c_4) = [1],
   pi(activate^#) = [1], pi(c_8) = [1], pi(sel^#) = [1], pi(c_9) = [1]
  
  Usable defined function symbols are a subset of:
  
   {first^#, activate^#, sel^#}
  
  For your convenience, here are the satisfied ordering constraints:
  
       pi(first^#(s(X), cons(Y, Z))) = first^#(cons(; Z);)           
                                     > c_4(activate^#(Z;);)          
                                     = pi(c_4(activate^#(Z)))        
                                                                     
    pi(activate^#(n__first(X1, X2))) = activate^#(n__first(; X2);)   
                                     > c_8(first^#(X2;);)            
                                     = pi(c_8(first^#(X1, X2)))      
                                                                     
         pi(sel^#(s(X), cons(Y, Z))) = sel^#(s(; X);)                
                                     > c_9(sel^#(X;);)               
                                     = pi(c_9(sel^#(X, activate(Z))))
                                                                     

The strictly oriented rules are moved into the weak component.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(1)).

Weak DPs:
  { first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
  , activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
  , sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z))) }
Weak Trs:
  { from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , first(X1, X2) -> n__first(X1, X2)
  , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
  , first(0(), Z) -> nil()
  , activate(X) -> X
  , activate(n__from(X)) -> from(X)
  , activate(n__first(X1, X2)) -> first(X1, X2) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(1))

The following weak DPs constitute a sub-graph of the DG that is
closed under successors. The DPs are removed.

{ first^#(s(X), cons(Y, Z)) -> c_4(activate^#(Z))
, activate^#(n__first(X1, X2)) -> c_8(first^#(X1, X2))
, sel^#(s(X), cons(Y, Z)) -> c_9(sel^#(X, activate(Z))) }

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(1)).

Weak Trs:
  { from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , first(X1, X2) -> n__first(X1, X2)
  , first(s(X), cons(Y, Z)) -> cons(Y, n__first(X, activate(Z)))
  , first(0(), Z) -> nil()
  , activate(X) -> X
  , activate(n__from(X)) -> from(X)
  , activate(n__first(X1, X2)) -> first(X1, X2) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(1))

No rule is usable, rules are removed from the input problem.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(1)).

Rules: Empty
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(1))

Empty rules are trivially bounded

Hurray, we answered YES(O(1),O(n^2))