MAYBE We are left with following problem, upon which TcT provides the certificate MAYBE. Strict Trs: { empty(nil()) -> true() , empty(cons(x, l)) -> false() , head(cons(x, l)) -> x , tail(nil()) -> nil() , tail(cons(x, l)) -> l , rev(nil()) -> nil() , rev(cons(x, l)) -> cons(rev1(x, l), rev2(x, l)) , rev2(x, nil()) -> nil() , rev2(x, cons(y, l)) -> rev(cons(x, rev2(y, l))) , last(x, l) -> if(empty(l), x, l) , if(true(), x, l) -> x , if(false(), x, l) -> last(head(l), tail(l)) } 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: { empty^#(nil()) -> c_1() , empty^#(cons(x, l)) -> c_2() , head^#(cons(x, l)) -> c_3(x) , tail^#(nil()) -> c_4() , tail^#(cons(x, l)) -> c_5(l) , rev^#(nil()) -> c_6() , rev^#(cons(x, l)) -> c_7(x, l, rev2^#(x, l)) , rev2^#(x, nil()) -> c_8() , rev2^#(x, cons(y, l)) -> c_9(rev^#(cons(x, rev2(y, l)))) , last^#(x, l) -> c_10(if^#(empty(l), x, l)) , if^#(true(), x, l) -> c_11(x) , if^#(false(), x, l) -> c_12(last^#(head(l), tail(l))) } and mark the set of starting terms. We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { empty^#(nil()) -> c_1() , empty^#(cons(x, l)) -> c_2() , head^#(cons(x, l)) -> c_3(x) , tail^#(nil()) -> c_4() , tail^#(cons(x, l)) -> c_5(l) , rev^#(nil()) -> c_6() , rev^#(cons(x, l)) -> c_7(x, l, rev2^#(x, l)) , rev2^#(x, nil()) -> c_8() , rev2^#(x, cons(y, l)) -> c_9(rev^#(cons(x, rev2(y, l)))) , last^#(x, l) -> c_10(if^#(empty(l), x, l)) , if^#(true(), x, l) -> c_11(x) , if^#(false(), x, l) -> c_12(last^#(head(l), tail(l))) } Strict Trs: { empty(nil()) -> true() , empty(cons(x, l)) -> false() , head(cons(x, l)) -> x , tail(nil()) -> nil() , tail(cons(x, l)) -> l , rev(nil()) -> nil() , rev(cons(x, l)) -> cons(rev1(x, l), rev2(x, l)) , rev2(x, nil()) -> nil() , rev2(x, cons(y, l)) -> rev(cons(x, rev2(y, l))) , last(x, l) -> if(empty(l), x, l) , if(true(), x, l) -> x , if(false(), x, l) -> last(head(l), tail(l)) } Obligation: runtime complexity Answer: MAYBE We estimate the number of application of {1,2,4,6,8} by applications of Pre({1,2,4,6,8}) = {3,5,7,11}. Here rules are labeled as follows: DPs: { 1: empty^#(nil()) -> c_1() , 2: empty^#(cons(x, l)) -> c_2() , 3: head^#(cons(x, l)) -> c_3(x) , 4: tail^#(nil()) -> c_4() , 5: tail^#(cons(x, l)) -> c_5(l) , 6: rev^#(nil()) -> c_6() , 7: rev^#(cons(x, l)) -> c_7(x, l, rev2^#(x, l)) , 8: rev2^#(x, nil()) -> c_8() , 9: rev2^#(x, cons(y, l)) -> c_9(rev^#(cons(x, rev2(y, l)))) , 10: last^#(x, l) -> c_10(if^#(empty(l), x, l)) , 11: if^#(true(), x, l) -> c_11(x) , 12: if^#(false(), x, l) -> c_12(last^#(head(l), tail(l))) } We are left with following problem, upon which TcT provides the certificate MAYBE. Strict DPs: { head^#(cons(x, l)) -> c_3(x) , tail^#(cons(x, l)) -> c_5(l) , rev^#(cons(x, l)) -> c_7(x, l, rev2^#(x, l)) , rev2^#(x, cons(y, l)) -> c_9(rev^#(cons(x, rev2(y, l)))) , last^#(x, l) -> c_10(if^#(empty(l), x, l)) , if^#(true(), x, l) -> c_11(x) , if^#(false(), x, l) -> c_12(last^#(head(l), tail(l))) } Strict Trs: { empty(nil()) -> true() , empty(cons(x, l)) -> false() , head(cons(x, l)) -> x , tail(nil()) -> nil() , tail(cons(x, l)) -> l , rev(nil()) -> nil() , rev(cons(x, l)) -> cons(rev1(x, l), rev2(x, l)) , rev2(x, nil()) -> nil() , rev2(x, cons(y, l)) -> rev(cons(x, rev2(y, l))) , last(x, l) -> if(empty(l), x, l) , if(true(), x, l) -> x , if(false(), x, l) -> last(head(l), tail(l)) } Weak DPs: { empty^#(nil()) -> c_1() , empty^#(cons(x, l)) -> c_2() , tail^#(nil()) -> c_4() , rev^#(nil()) -> c_6() , rev2^#(x, nil()) -> c_8() } Obligation: runtime complexity Answer: MAYBE Empty strict component of the problem is NOT empty. Arrrr..