MAYBE We are left with following problem, upon which TcT provides the certificate MAYBE. Strict Trs: { U11(tt(), N, X, XS) -> U12(splitAt(activate(N), activate(XS)), activate(X)) , U12(pair(YS, ZS), X) -> pair(cons(activate(X), YS), ZS) , splitAt(0(), XS) -> pair(nil(), XS) , splitAt(s(N), cons(X, XS)) -> U11(tt(), N, X, activate(XS)) , activate(X) -> X , activate(n__natsFrom(X)) -> natsFrom(activate(X)) , activate(n__s(X)) -> s(activate(X)) , afterNth(N, XS) -> snd(splitAt(N, XS)) , snd(pair(X, Y)) -> Y , and(tt(), X) -> activate(X) , fst(pair(X, Y)) -> X , head(cons(N, XS)) -> N , natsFrom(N) -> cons(N, n__natsFrom(n__s(N))) , natsFrom(X) -> n__natsFrom(X) , sel(N, XS) -> head(afterNth(N, XS)) , s(X) -> n__s(X) , tail(cons(N, XS)) -> activate(XS) , take(N, XS) -> fst(splitAt(N, XS)) } Obligation: runtime complexity Answer: MAYBE None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'WithProblem (timeout of 60 seconds)' failed due to the following reason: Computation stopped due to timeout after 60.0 seconds. 2) 'Best' failed due to the following reason: None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'WithProblem (timeout of 30 seconds) (timeout of 60 seconds)' failed due to the following reason: Computation stopped due to timeout after 30.0 seconds. 2) 'Best' failed due to the following reason: None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'bsearch-popstar (timeout of 60 seconds)' failed due to the following reason: The processor is inapplicable, reason: Processor only applicable for innermost runtime complexity analysis 2) 'Polynomial Path Order (PS) (timeout of 60 seconds)' failed due to the following reason: The processor is inapplicable, reason: Processor only applicable for innermost runtime complexity analysis 3) 'Fastest (timeout of 5 seconds) (timeout of 60 seconds)' failed due to the following reason: None of the processors succeeded. Details of failed attempt(s): ----------------------------- 1) 'Bounds with perSymbol-enrichment and initial automaton 'match'' failed due to the following reason: match-boundness of the problem could not be verified. 2) 'Bounds with minimal-enrichment and initial automaton 'match'' failed due to the following reason: match-boundness of the problem could not be verified. 3) 'Innermost Weak Dependency Pairs (timeout of 60 seconds)' failed due to the following reason: We add the following weak dependency pairs: Strict DPs: { U11^#(tt(), N, X, XS) -> c_1(U12^#(splitAt(activate(N), activate(XS)), activate(X))) , U12^#(pair(YS, ZS), X) -> c_2(activate^#(X), YS, ZS) , activate^#(X) -> c_5(X) , activate^#(n__natsFrom(X)) -> c_6(natsFrom^#(activate(X))) , activate^#(n__s(X)) -> c_7(s^#(activate(X))) , splitAt^#(0(), XS) -> c_3(XS) , splitAt^#(s(N), cons(X, XS)) -> c_4(U11^#(tt(), N, X, activate(XS))) , natsFrom^#(N) -> c_13(N, N) , natsFrom^#(X) -> c_14(X) , s^#(X) -> c_16(X) , afterNth^#(N, XS) -> c_8(snd^#(splitAt(N, XS))) , snd^#(pair(X, Y)) -> c_9(Y) , and^#(tt(), X) -> c_10(activate^#(X)) , fst^#(pair(X, Y)) -> c_11(X) , head^#(cons(N, XS)) -> c_12(N) , sel^#(N, XS) -> c_15(head^#(afterNth(N, XS))) , tail^#(cons(N, XS)) -> c_17(activate^#(XS)) , take^#(N, XS) -> c_18(fst^#(splitAt(N, XS))) } and mark the set of starting terms. We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { U11^#(tt(), N, X, XS) -> c_1(U12^#(splitAt(activate(N), activate(XS)), activate(X))) , U12^#(pair(YS, ZS), X) -> c_2(activate^#(X), YS, ZS) , activate^#(X) -> c_5(X) , activate^#(n__natsFrom(X)) -> c_6(natsFrom^#(activate(X))) , activate^#(n__s(X)) -> c_7(s^#(activate(X))) , splitAt^#(0(), XS) -> c_3(XS) , splitAt^#(s(N), cons(X, XS)) -> c_4(U11^#(tt(), N, X, activate(XS))) , natsFrom^#(N) -> c_13(N, N) , natsFrom^#(X) -> c_14(X) , s^#(X) -> c_16(X) , afterNth^#(N, XS) -> c_8(snd^#(splitAt(N, XS))) , snd^#(pair(X, Y)) -> c_9(Y) , and^#(tt(), X) -> c_10(activate^#(X)) , fst^#(pair(X, Y)) -> c_11(X) , head^#(cons(N, XS)) -> c_12(N) , sel^#(N, XS) -> c_15(head^#(afterNth(N, XS))) , tail^#(cons(N, XS)) -> c_17(activate^#(XS)) , take^#(N, XS) -> c_18(fst^#(splitAt(N, XS))) } Strict Trs: { U11(tt(), N, X, XS) -> U12(splitAt(activate(N), activate(XS)), activate(X)) , U12(pair(YS, ZS), X) -> pair(cons(activate(X), YS), ZS) , splitAt(0(), XS) -> pair(nil(), XS) , splitAt(s(N), cons(X, XS)) -> U11(tt(), N, X, activate(XS)) , activate(X) -> X , activate(n__natsFrom(X)) -> natsFrom(activate(X)) , activate(n__s(X)) -> s(activate(X)) , afterNth(N, XS) -> snd(splitAt(N, XS)) , snd(pair(X, Y)) -> Y , and(tt(), X) -> activate(X) , fst(pair(X, Y)) -> X , head(cons(N, XS)) -> N , natsFrom(N) -> cons(N, n__natsFrom(n__s(N))) , natsFrom(X) -> n__natsFrom(X) , sel(N, XS) -> head(afterNth(N, XS)) , s(X) -> n__s(X) , tail(cons(N, XS)) -> activate(XS) , take(N, XS) -> fst(splitAt(N, XS)) } Obligation: runtime complexity Answer: MAYBE Empty strict component of the problem is NOT empty. Arrrr..