*** 1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: Strict TRS Rules: gcd(0(),Y) -> 0() gcd(s(X),0()) -> s(X) gcd(s(X),s(Y)) -> if(le(Y,X),s(X),s(Y)) if(false(),s(X),s(Y)) -> gcd(minus(Y,X),s(X)) if(true(),s(X),s(Y)) -> gcd(minus(X,Y),s(Y)) le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Weak DP Rules: Weak TRS Rules: Signature: {gcd/2,if/3,le/2,minus/2,pred/1} / {0/0,false/0,s/1,true/0} Obligation: Innermost basic terms: {gcd,if,le,minus,pred}/{0,false,s,true} Applied Processor: DependencyPairs {dpKind_ = DT} Proof: We add the following dependency tuples: Strict DPs gcd#(0(),Y) -> c_1() gcd#(s(X),0()) -> c_2() gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(0(),Y) -> c_6() le#(s(X),0()) -> c_7() le#(s(X),s(Y)) -> c_8(le#(X,Y)) minus#(X,0()) -> c_9() minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)) pred#(s(X)) -> c_11() Weak DPs and mark the set of starting terms. *** 1.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(0(),Y) -> c_1() gcd#(s(X),0()) -> c_2() gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(0(),Y) -> c_6() le#(s(X),0()) -> c_7() le#(s(X),s(Y)) -> c_8(le#(X,Y)) minus#(X,0()) -> c_9() minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)) pred#(s(X)) -> c_11() Strict TRS Rules: Weak DP Rules: Weak TRS Rules: gcd(0(),Y) -> 0() gcd(s(X),0()) -> s(X) gcd(s(X),s(Y)) -> if(le(Y,X),s(X),s(Y)) if(false(),s(X),s(Y)) -> gcd(minus(Y,X),s(X)) if(true(),s(X),s(Y)) -> gcd(minus(X,Y),s(Y)) le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/2,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: UsableRules Proof: We replace rewrite rules by usable rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X gcd#(0(),Y) -> c_1() gcd#(s(X),0()) -> c_2() gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(0(),Y) -> c_6() le#(s(X),0()) -> c_7() le#(s(X),s(Y)) -> c_8(le#(X,Y)) minus#(X,0()) -> c_9() minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)) pred#(s(X)) -> c_11() *** 1.1.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(0(),Y) -> c_1() gcd#(s(X),0()) -> c_2() gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(0(),Y) -> c_6() le#(s(X),0()) -> c_7() le#(s(X),s(Y)) -> c_8(le#(X,Y)) minus#(X,0()) -> c_9() minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)) pred#(s(X)) -> c_11() Strict TRS Rules: Weak DP Rules: Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/2,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: PredecessorEstimation {onSelection = all simple predecessor estimation selector} Proof: We estimate the number of application of {1,2,6,7,9,11} by application of Pre({1,2,6,7,9,11}) = {3,4,5,8,10}. Here rules are labelled as follows: 1: gcd#(0(),Y) -> c_1() 2: gcd#(s(X),0()) -> c_2() 3: gcd#(s(X),s(Y)) -> c_3(if#(le(Y ,X) ,s(X) ,s(Y)) ,le#(Y,X)) 4: if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)) ,minus#(Y,X)) 5: if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)) ,minus#(X,Y)) 6: le#(0(),Y) -> c_6() 7: le#(s(X),0()) -> c_7() 8: le#(s(X),s(Y)) -> c_8(le#(X,Y)) 9: minus#(X,0()) -> c_9() 10: minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)) ,minus#(X,Y)) 11: pred#(s(X)) -> c_11() *** 1.1.1.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(s(X),s(Y)) -> c_8(le#(X,Y)) minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)) Strict TRS Rules: Weak DP Rules: gcd#(0(),Y) -> c_1() gcd#(s(X),0()) -> c_2() le#(0(),Y) -> c_6() le#(s(X),0()) -> c_7() minus#(X,0()) -> c_9() pred#(s(X)) -> c_11() Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/2,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: RemoveWeakSuffixes Proof: Consider the dependency graph 1:S:gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) -->_2 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 -->_1 if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)):3 -->_1 if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)):2 -->_2 le#(s(X),0()) -> c_7():9 -->_2 le#(0(),Y) -> c_6():8 2:S:if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) -->_2 minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)):5 -->_2 minus#(X,0()) -> c_9():10 -->_1 gcd#(0(),Y) -> c_1():6 -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 3:S:if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) -->_2 minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)):5 -->_2 minus#(X,0()) -> c_9():10 -->_1 gcd#(0(),Y) -> c_1():6 -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 4:S:le#(s(X),s(Y)) -> c_8(le#(X,Y)) -->_1 le#(s(X),0()) -> c_7():9 -->_1 le#(0(),Y) -> c_6():8 -->_1 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 5:S:minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)) -->_1 pred#(s(X)) -> c_11():11 -->_2 minus#(X,0()) -> c_9():10 -->_2 minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)):5 6:W:gcd#(0(),Y) -> c_1() 7:W:gcd#(s(X),0()) -> c_2() 8:W:le#(0(),Y) -> c_6() 9:W:le#(s(X),0()) -> c_7() 10:W:minus#(X,0()) -> c_9() 11:W:pred#(s(X)) -> c_11() The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed. 7: gcd#(s(X),0()) -> c_2() 6: gcd#(0(),Y) -> c_1() 10: minus#(X,0()) -> c_9() 11: pred#(s(X)) -> c_11() 8: le#(0(),Y) -> c_6() 9: le#(s(X),0()) -> c_7() *** 1.1.1.1.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(s(X),s(Y)) -> c_8(le#(X,Y)) minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/2,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: SimplifyRHS Proof: Consider the dependency graph 1:S:gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) -->_2 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 -->_1 if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)):3 -->_1 if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)):2 2:S:if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) -->_2 minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)):5 -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 3:S:if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) -->_2 minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)):5 -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 4:S:le#(s(X),s(Y)) -> c_8(le#(X,Y)) -->_1 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 5:S:minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)) -->_2 minus#(X,s(Y)) -> c_10(pred#(minus(X,Y)),minus#(X,Y)):5 Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified: minus#(X,s(Y)) -> c_10(minus#(X,Y)) *** 1.1.1.1.1.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(s(X),s(Y)) -> c_8(le#(X,Y)) minus#(X,s(Y)) -> c_10(minus#(X,Y)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} 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, greedy = NoGreedy}} Proof: We first use the processor NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Nothing, greedy = NoGreedy} to orient following rules strictly: 5: minus#(X,s(Y)) -> c_10(minus#(X ,Y)) The strictly oriented rules are moved into the weak component. *** 1.1.1.1.1.1.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(s(X),s(Y)) -> c_8(le#(X,Y)) minus#(X,s(Y)) -> c_10(minus#(X,Y)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: NaturalPI {shape = Mixed 2, restrict = Restrict, uargs = UArgs, urules = URules, selector = Just first alternative for predecessorEstimation any intersect of rules of CDG leaf and strict-rules, greedy = NoGreedy} Proof: We apply a polynomial interpretation of kind constructor-based(mixed(2)): The following argument positions are considered usable: uargs(c_3) = {1,2}, uargs(c_4) = {1,2}, uargs(c_5) = {1,2}, uargs(c_8) = {1}, uargs(c_10) = {1} Following symbols are considered usable: {minus,pred,gcd#,if#,le#,minus#,pred#} TcT has computed the following interpretation: p(0) = 0 p(false) = 0 p(gcd) = 2*x1^2 + 2*x2^2 p(if) = 2*x1^2 p(le) = x1*x2 + 2*x2 + x2^2 p(minus) = x1 p(pred) = x1 p(s) = 1 + x1 p(true) = 0 p(gcd#) = 3 + 2*x1*x2 p(if#) = 1 + 2*x2*x3 p(le#) = 2 p(minus#) = x2 p(pred#) = 2 p(c_1) = 1 p(c_2) = 0 p(c_3) = x1 + x2 p(c_4) = x1 + x2 p(c_5) = x1 + x2 p(c_6) = 1 p(c_7) = 0 p(c_8) = x1 p(c_9) = 0 p(c_10) = x1 p(c_11) = 1 Following rules are strictly oriented: minus#(X,s(Y)) = 1 + Y > Y = c_10(minus#(X,Y)) Following rules are (at-least) weakly oriented: gcd#(s(X),s(Y)) = 5 + 2*X + 2*X*Y + 2*Y >= 5 + 2*X + 2*X*Y + 2*Y = c_3(if#(le(Y,X),s(X),s(Y)) ,le#(Y,X)) if#(false(),s(X),s(Y)) = 3 + 2*X + 2*X*Y + 2*Y >= 3 + X + 2*X*Y + 2*Y = c_4(gcd#(minus(Y,X),s(X)) ,minus#(Y,X)) if#(true(),s(X),s(Y)) = 3 + 2*X + 2*X*Y + 2*Y >= 3 + 2*X + 2*X*Y + Y = c_5(gcd#(minus(X,Y),s(Y)) ,minus#(X,Y)) le#(s(X),s(Y)) = 2 >= 2 = c_8(le#(X,Y)) minus(X,0()) = X >= X = X minus(X,s(Y)) = X >= X = pred(minus(X,Y)) pred(s(X)) = 1 + X >= X = X *** 1.1.1.1.1.1.1.1 Progress [(?,O(1))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(s(X),s(Y)) -> c_8(le#(X,Y)) Strict TRS Rules: Weak DP Rules: minus#(X,s(Y)) -> c_10(minus#(X,Y)) Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: Assumption Proof: () *** 1.1.1.1.1.1.2 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(s(X),s(Y)) -> c_8(le#(X,Y)) Strict TRS Rules: Weak DP Rules: minus#(X,s(Y)) -> c_10(minus#(X,Y)) Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: RemoveWeakSuffixes Proof: Consider the dependency graph 1:S:gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) -->_2 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 -->_1 if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)):3 -->_1 if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)):2 2:S:if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) -->_2 minus#(X,s(Y)) -> c_10(minus#(X,Y)):5 -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 3:S:if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) -->_2 minus#(X,s(Y)) -> c_10(minus#(X,Y)):5 -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 4:S:le#(s(X),s(Y)) -> c_8(le#(X,Y)) -->_1 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 5:W:minus#(X,s(Y)) -> c_10(minus#(X,Y)) -->_1 minus#(X,s(Y)) -> c_10(minus#(X,Y)):5 The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed. 5: minus#(X,s(Y)) -> c_10(minus#(X ,Y)) *** 1.1.1.1.1.1.2.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) le#(s(X),s(Y)) -> c_8(le#(X,Y)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/2,c_5/2,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: SimplifyRHS Proof: Consider the dependency graph 1:S:gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) -->_2 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 -->_1 if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)):3 -->_1 if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)):2 2:S:if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X)),minus#(Y,X)) -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 3:S:if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y)),minus#(X,Y)) -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 4:S:le#(s(X),s(Y)) -> c_8(le#(X,Y)) -->_1 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified: if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) *** 1.1.1.1.1.1.2.1.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) le#(s(X),s(Y)) -> c_8(le#(X,Y)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/1,c_5/1,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: PredecessorEstimationCP {onSelectionCP = any intersect of rules of CDG leaf and strict-rules, withComplexityPair = NaturalMI {miDimension = 3, miDegree = 2, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing, greedy = NoGreedy}} Proof: We first use the processor NaturalMI {miDimension = 3, miDegree = 2, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing, greedy = NoGreedy} to orient following rules strictly: 2: if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) 3: if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) 4: le#(s(X),s(Y)) -> c_8(le#(X,Y)) Consider the set of all dependency pairs 1: gcd#(s(X),s(Y)) -> c_3(if#(le(Y ,X) ,s(X) ,s(Y)) ,le#(Y,X)) 2: if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) 3: if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) 4: le#(s(X),s(Y)) -> c_8(le#(X,Y)) Processor NaturalMI {miDimension = 3, miDegree = 2, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing, greedy = NoGreedy}induces the complexity certificateTIME (?,O(n^2)) SPACE(?,?)on application of the dependency pairs {2,3,4} 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. *** 1.1.1.1.1.1.2.1.1.1 Progress [(?,O(n^2))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) le#(s(X),s(Y)) -> c_8(le#(X,Y)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/1,c_5/1,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: NaturalMI {miDimension = 3, miDegree = 2, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Just first alternative for predecessorEstimation any intersect of rules of CDG leaf and strict-rules, greedy = NoGreedy} Proof: We apply a matrix interpretation of kind constructor based matrix interpretation (containing no more than 2 non-zero interpretation-entries in the diagonal of the component-wise maxima): The following argument positions are considered usable: uargs(c_3) = {1,2}, uargs(c_4) = {1}, uargs(c_5) = {1}, uargs(c_8) = {1} Following symbols are considered usable: {minus,pred,gcd#,if#,le#,minus#,pred#} TcT has computed the following interpretation: p(0) = [0] [0] [0] p(false) = [0] [0] [0] p(gcd) = [0] [0] [0] p(if) = [0] [0] [0] p(le) = [0 0 0] [0] [0 0 0] x2 + [0] [0 0 1] [0] p(minus) = [1 0 0] [0] [1 1 0] x1 + [0] [0 1 1] [0] p(pred) = [1 0 0] [0] [1 0 0] x1 + [0] [0 0 1] [0] p(s) = [1 1 1] [0] [0 0 0] x1 + [1] [0 0 1] [1] p(true) = [0] [0] [0] p(gcd#) = [1 0 1] [1 0 0] [0] [0 0 0] x1 + [0 1 1] x2 + [0] [0 0 0] [0 1 0] [1] p(if#) = [1 0 0] [1 1 0] [0] [0 0 0] x2 + [0 1 0] x3 + [1] [1 0 0] [1 0 0] [0] p(le#) = [0 0 0] [0 0 1] [0] [0 0 1] x1 + [0 1 0] x2 + [0] [0 0 0] [0 0 0] [1] p(minus#) = [0] [0] [0] p(pred#) = [0] [0] [0] p(c_1) = [0] [0] [0] p(c_2) = [0] [0] [0] p(c_3) = [1 0 0] [1 0 0] [0] [0 0 0] x1 + [0 0 1] x2 + [1] [0 0 0] [0 0 0] [0] p(c_4) = [1 0 0] [0] [0 0 1] x1 + [0] [1 0 0] [0] p(c_5) = [1 0 0] [0] [0 0 0] x1 + [0] [0 0 0] [0] p(c_6) = [0] [0] [0] p(c_7) = [0] [0] [0] p(c_8) = [1 0 0] [0] [0 0 0] x1 + [1] [0 0 0] [0] p(c_9) = [0] [0] [0] p(c_10) = [0] [0] [0] p(c_11) = [0] [0] [0] Following rules are strictly oriented: if#(false(),s(X),s(Y)) = [1 1 1] [1 1 1] [1] [0 0 0] X + [0 0 0] Y + [2] [1 1 1] [1 1 1] [0] > [1 1 1] [1 1 1] [0] [0 0 0] X + [0 0 0] Y + [2] [1 1 1] [1 1 1] [0] = c_4(gcd#(minus(Y,X),s(X))) if#(true(),s(X),s(Y)) = [1 1 1] [1 1 1] [1] [0 0 0] X + [0 0 0] Y + [2] [1 1 1] [1 1 1] [0] > [1 1 1] [1 1 1] [0] [0 0 0] X + [0 0 0] Y + [0] [0 0 0] [0 0 0] [0] = c_5(gcd#(minus(X,Y),s(Y))) le#(s(X),s(Y)) = [0 0 0] [0 0 1] [1] [0 0 1] X + [0 0 0] Y + [2] [0 0 0] [0 0 0] [1] > [0 0 1] [0] [0 0 0] Y + [1] [0 0 0] [0] = c_8(le#(X,Y)) Following rules are (at-least) weakly oriented: gcd#(s(X),s(Y)) = [1 1 2] [1 1 1] [1] [0 0 0] X + [0 0 1] Y + [2] [0 0 0] [0 0 0] [2] >= [1 1 2] [1 1 1] [1] [0 0 0] X + [0 0 0] Y + [2] [0 0 0] [0 0 0] [0] = c_3(if#(le(Y,X),s(X),s(Y)) ,le#(Y,X)) minus(X,0()) = [1 0 0] [0] [1 1 0] X + [0] [0 1 1] [0] >= [1 0 0] [0] [0 1 0] X + [0] [0 0 1] [0] = X minus(X,s(Y)) = [1 0 0] [0] [1 1 0] X + [0] [0 1 1] [0] >= [1 0 0] [0] [1 0 0] X + [0] [0 1 1] [0] = pred(minus(X,Y)) pred(s(X)) = [1 1 1] [0] [1 1 1] X + [0] [0 0 1] [1] >= [1 0 0] [0] [0 1 0] X + [0] [0 0 1] [0] = X *** 1.1.1.1.1.1.2.1.1.1.1 Progress [(?,O(1))] *** Considered Problem: Strict DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) Strict TRS Rules: Weak DP Rules: if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) le#(s(X),s(Y)) -> c_8(le#(X,Y)) Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/1,c_5/1,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: Assumption Proof: () *** 1.1.1.1.1.1.2.1.1.2 Progress [(O(1),O(1))] *** Considered Problem: Strict DP Rules: Strict TRS Rules: Weak DP Rules: gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) le#(s(X),s(Y)) -> c_8(le#(X,Y)) Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/1,c_5/1,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: RemoveWeakSuffixes Proof: Consider the dependency graph 1:W:gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)) -->_2 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 -->_1 if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))):3 -->_1 if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))):2 2:W:if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 3:W:if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) -->_1 gcd#(s(X),s(Y)) -> c_3(if#(le(Y,X),s(X),s(Y)),le#(Y,X)):1 4:W:le#(s(X),s(Y)) -> c_8(le#(X,Y)) -->_1 le#(s(X),s(Y)) -> c_8(le#(X,Y)):4 The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed. 1: gcd#(s(X),s(Y)) -> c_3(if#(le(Y ,X) ,s(X) ,s(Y)) ,le#(Y,X)) 3: if#(true(),s(X),s(Y)) -> c_5(gcd#(minus(X,Y),s(Y))) 2: if#(false(),s(X),s(Y)) -> c_4(gcd#(minus(Y,X),s(X))) 4: le#(s(X),s(Y)) -> c_8(le#(X,Y)) *** 1.1.1.1.1.1.2.1.1.2.1 Progress [(O(1),O(1))] *** Considered Problem: Strict DP Rules: Strict TRS Rules: Weak DP Rules: Weak TRS Rules: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(X,0()) -> X minus(X,s(Y)) -> pred(minus(X,Y)) pred(s(X)) -> X Signature: {gcd/2,if/3,le/2,minus/2,pred/1,gcd#/2,if#/3,le#/2,minus#/2,pred#/1} / {0/0,false/0,s/1,true/0,c_1/0,c_2/0,c_3/2,c_4/1,c_5/1,c_6/0,c_7/0,c_8/1,c_9/0,c_10/1,c_11/0} Obligation: Innermost basic terms: {gcd#,if#,le#,minus#,pred#}/{0,false,s,true} Applied Processor: EmptyProcessor Proof: The problem is already closed. The intended complexity is O(1).