*** 1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: Strict TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) fst(pair(XS,YS)) -> XS head(cons(N,XS)) -> N natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) sel(N,XS) -> head(afterNth(N,XS)) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) tail(cons(N,XS)) -> activate(XS) take(N,XS) -> fst(splitAt(N,XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) Weak DP Rules: Weak TRS Rules: Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1} Obligation: Innermost basic terms: {activate,afterNth,fst,head,natsFrom,sel,snd,splitAt,tail,take,u}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: DependencyPairs {dpKind_ = DT} Proof: We add the following dependency tuples: Strict DPs activate#(X) -> c_1() activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) fst#(pair(XS,YS)) -> c_4() head#(cons(N,XS)) -> c_5() natsFrom#(N) -> c_6() natsFrom#(X) -> c_7() sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) snd#(pair(XS,YS)) -> c_9() splitAt#(0(),XS) -> c_10() splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) tail#(cons(N,XS)) -> c_12(activate#(XS)) take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) Weak DPs and mark the set of starting terms. *** 1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: activate#(X) -> c_1() activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) fst#(pair(XS,YS)) -> c_4() head#(cons(N,XS)) -> c_5() natsFrom#(N) -> c_6() natsFrom#(X) -> c_7() sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) snd#(pair(XS,YS)) -> c_9() splitAt#(0(),XS) -> c_10() splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) tail#(cons(N,XS)) -> c_12(activate#(XS)) take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) fst(pair(XS,YS)) -> XS head(cons(N,XS)) -> N natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) sel(N,XS) -> head(afterNth(N,XS)) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) tail(cons(N,XS)) -> activate(XS) take(N,XS) -> fst(splitAt(N,XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/2,c_4/0,c_5/0,c_6/0,c_7/0,c_8/2,c_9/0,c_10/0,c_11/4,c_12/1,c_13/2,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: UsableRules Proof: We replace rewrite rules by usable rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) activate#(X) -> c_1() activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) fst#(pair(XS,YS)) -> c_4() head#(cons(N,XS)) -> c_5() natsFrom#(N) -> c_6() natsFrom#(X) -> c_7() sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) snd#(pair(XS,YS)) -> c_9() splitAt#(0(),XS) -> c_10() splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) tail#(cons(N,XS)) -> c_12(activate#(XS)) take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) *** 1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: activate#(X) -> c_1() activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) fst#(pair(XS,YS)) -> c_4() head#(cons(N,XS)) -> c_5() natsFrom#(N) -> c_6() natsFrom#(X) -> c_7() sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) snd#(pair(XS,YS)) -> c_9() splitAt#(0(),XS) -> c_10() splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) tail#(cons(N,XS)) -> c_12(activate#(XS)) take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/2,c_4/0,c_5/0,c_6/0,c_7/0,c_8/2,c_9/0,c_10/0,c_11/4,c_12/1,c_13/2,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: PredecessorEstimation {onSelection = all simple predecessor estimation selector} Proof: We estimate the number of application of {1,4,5,6,7,9,10} by application of Pre({1,4,5,6,7,9,10}) = {2,3,8,11,12,13,14}. Here rules are labelled as follows: 1: activate#(X) -> c_1() 2: activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) 3: afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)) ,splitAt#(N,XS)) 4: fst#(pair(XS,YS)) -> c_4() 5: head#(cons(N,XS)) -> c_5() 6: natsFrom#(N) -> c_6() 7: natsFrom#(X) -> c_7() 8: sel#(N,XS) -> c_8(head#(afterNth(N,XS)) ,afterNth#(N,XS)) 9: snd#(pair(XS,YS)) -> c_9() 10: splitAt#(0(),XS) -> c_10() 11: splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)) ,N ,X ,activate(XS)) ,splitAt#(N,activate(XS)) ,activate#(XS) ,activate#(XS)) 12: tail#(cons(N,XS)) -> c_12(activate#(XS)) 13: take#(N,XS) -> c_13(fst#(splitAt(N,XS)) ,splitAt#(N,XS)) 14: u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) *** 1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) tail#(cons(N,XS)) -> c_12(activate#(XS)) take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) Strict TRS Rules: Weak DP Rules: activate#(X) -> c_1() fst#(pair(XS,YS)) -> c_4() head#(cons(N,XS)) -> c_5() natsFrom#(N) -> c_6() natsFrom#(X) -> c_7() snd#(pair(XS,YS)) -> c_9() splitAt#(0(),XS) -> c_10() Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/2,c_4/0,c_5/0,c_6/0,c_7/0,c_8/2,c_9/0,c_10/0,c_11/4,c_12/1,c_13/2,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: PredecessorEstimation {onSelection = all simple predecessor estimation selector} Proof: We estimate the number of application of {1} by application of Pre({1}) = {4,5,7}. Here rules are labelled as follows: 1: activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) 2: afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)) ,splitAt#(N,XS)) 3: sel#(N,XS) -> c_8(head#(afterNth(N,XS)) ,afterNth#(N,XS)) 4: splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)) ,N ,X ,activate(XS)) ,splitAt#(N,activate(XS)) ,activate#(XS) ,activate#(XS)) 5: tail#(cons(N,XS)) -> c_12(activate#(XS)) 6: take#(N,XS) -> c_13(fst#(splitAt(N,XS)) ,splitAt#(N,XS)) 7: u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) 8: activate#(X) -> c_1() 9: fst#(pair(XS,YS)) -> c_4() 10: head#(cons(N,XS)) -> c_5() 11: natsFrom#(N) -> c_6() 12: natsFrom#(X) -> c_7() 13: snd#(pair(XS,YS)) -> c_9() 14: splitAt#(0(),XS) -> c_10() *** 1.1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) tail#(cons(N,XS)) -> c_12(activate#(XS)) take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) Strict TRS Rules: Weak DP Rules: activate#(X) -> c_1() activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) fst#(pair(XS,YS)) -> c_4() head#(cons(N,XS)) -> c_5() natsFrom#(N) -> c_6() natsFrom#(X) -> c_7() snd#(pair(XS,YS)) -> c_9() splitAt#(0(),XS) -> c_10() Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/2,c_4/0,c_5/0,c_6/0,c_7/0,c_8/2,c_9/0,c_10/0,c_11/4,c_12/1,c_13/2,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: PredecessorEstimation {onSelection = all simple predecessor estimation selector} Proof: We estimate the number of application of {4,6} by application of Pre({4,6}) = {3}. Here rules are labelled as follows: 1: afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)) ,splitAt#(N,XS)) 2: sel#(N,XS) -> c_8(head#(afterNth(N,XS)) ,afterNth#(N,XS)) 3: splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)) ,N ,X ,activate(XS)) ,splitAt#(N,activate(XS)) ,activate#(XS) ,activate#(XS)) 4: tail#(cons(N,XS)) -> c_12(activate#(XS)) 5: take#(N,XS) -> c_13(fst#(splitAt(N,XS)) ,splitAt#(N,XS)) 6: u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) 7: activate#(X) -> c_1() 8: activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) 9: fst#(pair(XS,YS)) -> c_4() 10: head#(cons(N,XS)) -> c_5() 11: natsFrom#(N) -> c_6() 12: natsFrom#(X) -> c_7() 13: snd#(pair(XS,YS)) -> c_9() 14: splitAt#(0(),XS) -> c_10() *** 1.1.1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) Strict TRS Rules: Weak DP Rules: activate#(X) -> c_1() activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) fst#(pair(XS,YS)) -> c_4() head#(cons(N,XS)) -> c_5() natsFrom#(N) -> c_6() natsFrom#(X) -> c_7() snd#(pair(XS,YS)) -> c_9() splitAt#(0(),XS) -> c_10() tail#(cons(N,XS)) -> c_12(activate#(XS)) u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/2,c_4/0,c_5/0,c_6/0,c_7/0,c_8/2,c_9/0,c_10/0,c_11/4,c_12/1,c_13/2,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: RemoveWeakSuffixes Proof: Consider the dependency graph 1:S:afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) -->_2 splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)):3 -->_2 splitAt#(0(),XS) -> c_10():12 -->_1 snd#(pair(XS,YS)) -> c_9():11 2:S:sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) -->_1 head#(cons(N,XS)) -> c_5():8 -->_2 afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)):1 3:S:splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) -->_1 u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)):14 -->_4 activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)):6 -->_3 activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)):6 -->_2 splitAt#(0(),XS) -> c_10():12 -->_4 activate#(X) -> c_1():5 -->_3 activate#(X) -> c_1():5 -->_2 splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)):3 4:S:take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) -->_2 splitAt#(0(),XS) -> c_10():12 -->_1 fst#(pair(XS,YS)) -> c_4():7 -->_2 splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)):3 5:W:activate#(X) -> c_1() 6:W:activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) -->_1 natsFrom#(X) -> c_7():10 -->_1 natsFrom#(N) -> c_6():9 7:W:fst#(pair(XS,YS)) -> c_4() 8:W:head#(cons(N,XS)) -> c_5() 9:W:natsFrom#(N) -> c_6() 10:W:natsFrom#(X) -> c_7() 11:W:snd#(pair(XS,YS)) -> c_9() 12:W:splitAt#(0(),XS) -> c_10() 13:W:tail#(cons(N,XS)) -> c_12(activate#(XS)) -->_1 activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)):6 -->_1 activate#(X) -> c_1():5 14:W:u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) -->_1 activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)):6 -->_1 activate#(X) -> c_1():5 The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed. 13: tail#(cons(N,XS)) -> c_12(activate#(XS)) 7: fst#(pair(XS,YS)) -> c_4() 8: head#(cons(N,XS)) -> c_5() 11: snd#(pair(XS,YS)) -> c_9() 12: splitAt#(0(),XS) -> c_10() 14: u#(pair(YS,ZS),N,X,XS) -> c_14(activate#(X)) 5: activate#(X) -> c_1() 6: activate#(n__natsFrom(X)) -> c_2(natsFrom#(X)) 9: natsFrom#(N) -> c_6() 10: natsFrom#(X) -> c_7() *** 1.1.1.1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/2,c_4/0,c_5/0,c_6/0,c_7/0,c_8/2,c_9/0,c_10/0,c_11/4,c_12/1,c_13/2,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: SimplifyRHS Proof: Consider the dependency graph 1:S:afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)) -->_2 splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)):3 2:S:sel#(N,XS) -> c_8(head#(afterNth(N,XS)),afterNth#(N,XS)) -->_2 afterNth#(N,XS) -> c_3(snd#(splitAt(N,XS)),splitAt#(N,XS)):1 3:S:splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)) -->_2 splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)):3 4:S:take#(N,XS) -> c_13(fst#(splitAt(N,XS)),splitAt#(N,XS)) -->_2 splitAt#(s(N),cons(X,XS)) -> c_11(u#(splitAt(N,activate(XS)),N,X,activate(XS)),splitAt#(N,activate(XS)),activate#(XS),activate#(XS)):3 Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified: afterNth#(N,XS) -> c_3(splitAt#(N,XS)) sel#(N,XS) -> c_8(afterNth#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) take#(N,XS) -> c_13(splitAt#(N,XS)) *** 1.1.1.1.1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: afterNth#(N,XS) -> c_3(splitAt#(N,XS)) sel#(N,XS) -> c_8(afterNth#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) take#(N,XS) -> c_13(splitAt#(N,XS)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) afterNth(N,XS) -> snd(splitAt(N,XS)) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) snd(pair(XS,YS)) -> YS splitAt(0(),XS) -> pair(nil(),XS) splitAt(s(N),cons(X,XS)) -> u(splitAt(N,activate(XS)),N,X,activate(XS)) u(pair(YS,ZS),N,X,XS) -> pair(cons(activate(X),YS),ZS) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/1,c_4/0,c_5/0,c_6/0,c_7/0,c_8/1,c_9/0,c_10/0,c_11/1,c_12/1,c_13/1,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: UsableRules Proof: We replace rewrite rules by usable rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) afterNth#(N,XS) -> c_3(splitAt#(N,XS)) sel#(N,XS) -> c_8(afterNth#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) take#(N,XS) -> c_13(splitAt#(N,XS)) *** 1.1.1.1.1.1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: afterNth#(N,XS) -> c_3(splitAt#(N,XS)) sel#(N,XS) -> c_8(afterNth#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) take#(N,XS) -> c_13(splitAt#(N,XS)) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/1,c_4/0,c_5/0,c_6/0,c_7/0,c_8/1,c_9/0,c_10/0,c_11/1,c_12/1,c_13/1,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: RemoveHeads Proof: Consider the dependency graph 1:S:afterNth#(N,XS) -> c_3(splitAt#(N,XS)) -->_1 splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))):3 2:S:sel#(N,XS) -> c_8(afterNth#(N,XS)) -->_1 afterNth#(N,XS) -> c_3(splitAt#(N,XS)):1 3:S:splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) -->_1 splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))):3 4:S:take#(N,XS) -> c_13(splitAt#(N,XS)) -->_1 splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))):3 Following roots of the dependency graph are removed, as the considered set of starting terms is closed under reduction with respect to these rules (modulo compound contexts). [(2,sel#(N,XS) -> c_8(afterNth#(N,XS))),(4,take#(N,XS) -> c_13(splitAt#(N,XS)))] *** 1.1.1.1.1.1.1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: afterNth#(N,XS) -> c_3(splitAt#(N,XS)) splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/1,c_4/0,c_5/0,c_6/0,c_7/0,c_8/1,c_9/0,c_10/0,c_11/1,c_12/1,c_13/1,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: RemoveHeads Proof: Consider the dependency graph 1:S:afterNth#(N,XS) -> c_3(splitAt#(N,XS)) -->_1 splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))):3 3:S:splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) -->_1 splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))):3 Following roots of the dependency graph are removed, as the considered set of starting terms is closed under reduction with respect to these rules (modulo compound contexts). [(1,afterNth#(N,XS) -> c_3(splitAt#(N,XS)))] *** 1.1.1.1.1.1.1.1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/1,c_4/0,c_5/0,c_6/0,c_7/0,c_8/1,c_9/0,c_10/0,c_11/1,c_12/1,c_13/1,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} 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, greedy = NoGreedy}} Proof: We first use the processor NaturalMI {miDimension = 1, miDegree = 1, miKind = Algebraic, uargs = UArgs, urules = URules, selector = Nothing, greedy = NoGreedy} to orient following rules strictly: 3: splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) The strictly oriented rules are moved into the weak component. *** 1.1.1.1.1.1.1.1.1.1.1.1 Progress [(?,O(n^1))] *** Considered Problem: Strict DP Rules: splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/1,c_4/0,c_5/0,c_6/0,c_7/0,c_8/1,c_9/0,c_10/0,c_11/1,c_12/1,c_13/1,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: NaturalMI {miDimension = 1, miDegree = 1, 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: The following argument positions are considered usable: uargs(c_11) = {1} Following symbols are considered usable: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#} TcT has computed the following interpretation: p(0) = [1] p(activate) = [0] p(afterNth) = [1] x1 + [1] x2 + [0] p(cons) = [1] x1 + [0] p(fst) = [1] x1 + [1] p(head) = [2] x1 + [4] p(n__natsFrom) = [0] p(natsFrom) = [0] p(nil) = [2] p(pair) = [8] p(s) = [1] x1 + [6] p(sel) = [2] x2 + [0] p(snd) = [1] x1 + [2] p(splitAt) = [1] x1 + [1] x2 + [2] p(tail) = [1] x1 + [0] p(take) = [1] x1 + [4] p(u) = [1] x1 + [8] x3 + [0] p(activate#) = [1] x1 + [1] p(afterNth#) = [1] x1 + [4] p(fst#) = [0] p(head#) = [4] p(natsFrom#) = [2] x1 + [1] p(sel#) = [1] x1 + [0] p(snd#) = [2] p(splitAt#) = [1] x1 + [0] p(tail#) = [8] p(take#) = [1] p(u#) = [8] x1 + [1] x2 + [1] p(c_1) = [2] p(c_2) = [8] x1 + [1] p(c_3) = [1] p(c_4) = [1] p(c_5) = [0] p(c_6) = [0] p(c_7) = [1] p(c_8) = [4] p(c_9) = [2] p(c_10) = [2] p(c_11) = [1] x1 + [0] p(c_12) = [0] p(c_13) = [1] p(c_14) = [1] x1 + [1] Following rules are strictly oriented: splitAt#(s(N),cons(X,XS)) = [1] N + [6] > [1] N + [0] = c_11(splitAt#(N,activate(XS))) Following rules are (at-least) weakly oriented: *** 1.1.1.1.1.1.1.1.1.1.1.1.1 Progress [(?,O(1))] *** Considered Problem: Strict DP Rules: Strict TRS Rules: Weak DP Rules: splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/1,c_4/0,c_5/0,c_6/0,c_7/0,c_8/1,c_9/0,c_10/0,c_11/1,c_12/1,c_13/1,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: Assumption Proof: () *** 1.1.1.1.1.1.1.1.1.1.1.2 Progress [(O(1),O(1))] *** Considered Problem: Strict DP Rules: Strict TRS Rules: Weak DP Rules: splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/1,c_4/0,c_5/0,c_6/0,c_7/0,c_8/1,c_9/0,c_10/0,c_11/1,c_12/1,c_13/1,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: RemoveWeakSuffixes Proof: Consider the dependency graph 1:W:splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) -->_1 splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))):1 The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed. 1: splitAt#(s(N),cons(X,XS)) -> c_11(splitAt#(N,activate(XS))) *** 1.1.1.1.1.1.1.1.1.1.1.2.1 Progress [(O(1),O(1))] *** Considered Problem: Strict DP Rules: Strict TRS Rules: Weak DP Rules: Weak TRS Rules: activate(X) -> X activate(n__natsFrom(X)) -> natsFrom(X) natsFrom(N) -> cons(N,n__natsFrom(s(N))) natsFrom(X) -> n__natsFrom(X) Signature: {activate/1,afterNth/2,fst/1,head/1,natsFrom/1,sel/2,snd/1,splitAt/2,tail/1,take/2,u/4,activate#/1,afterNth#/2,fst#/1,head#/1,natsFrom#/1,sel#/2,snd#/1,splitAt#/2,tail#/1,take#/2,u#/4} / {0/0,cons/2,n__natsFrom/1,nil/0,pair/2,s/1,c_1/0,c_2/1,c_3/1,c_4/0,c_5/0,c_6/0,c_7/0,c_8/1,c_9/0,c_10/0,c_11/1,c_12/1,c_13/1,c_14/1} Obligation: Innermost basic terms: {activate#,afterNth#,fst#,head#,natsFrom#,sel#,snd#,splitAt#,tail#,take#,u#}/{0,cons,n__natsFrom,nil,pair,s} Applied Processor: EmptyProcessor Proof: The problem is already closed. The intended complexity is O(1).