YES(?,POLY) 'Pop* with parameter subtitution (timeout of 60.0 seconds)' ----------------------------------------------------------- Answer: YES(?,POLY) Input Problem: innermost runtime-complexity with respect to Rules: { first(0(), X) -> nil() , first(s(X), cons(Y)) -> cons(Y) , from(X) -> cons(X)} Proof Output: The input was oriented with the instance of POP* as induced by the precedence first ~ from and safe mapping safe(first) = {1}, safe(0) = {}, safe(nil) = {}, safe(s) = {1}, safe(cons) = {1}, safe(from) = {} . For your convenience, here is the input in predicative notation: Rules: { first(X; 0()) -> nil() , first(cons(; Y); s(; X)) -> cons(; Y) , from(X;) -> cons(; X)}