YES(?,POLY) 'Pop* with parameter subtitution (timeout of 60.0 seconds)' ----------------------------------------------------------- Answer: YES(?,POLY) Input Problem: innermost runtime-complexity with respect to Rules: { sum(0()) -> 0() , sum(s(x)) -> +(sum(x), s(x)) , sum1(0()) -> 0() , sum1(s(x)) -> s(+(sum1(x), +(x, x)))} Proof Output: The input was oriented with the instance of POP* as induced by the precedence sum ~ sum1 and safe mapping safe(sum) = {}, safe(0) = {}, safe(s) = {1}, safe(+) = {1, 2}, safe(sum1) = {} . For your convenience, here is the input in predicative notation: Rules: { sum(0();) -> 0() , sum(s(; x);) -> +(; sum(x;), s(; x)) , sum1(0();) -> 0() , sum1(s(; x);) -> s(; +(; sum1(x;), +(; x, x)))}