MAYBE We are left with following problem, upon which TcT provides the certificate MAYBE. Strict Trs: { fac(0()) -> 1() , fac(0()) -> s(0()) , fac(s(x)) -> *(s(x), fac(x)) , 1() -> s(0()) , *(x, 0()) -> 0() , *(x, s(y)) -> +(*(x, y), x) , floop(0(), y) -> y , floop(s(x), y) -> floop(x, *(s(x), y)) , +(x, 0()) -> x , +(x, s(y)) -> s(+(x, y)) } Obligation: innermost runtime complexity Answer: MAYBE The input cannot be shown compatible Arrrr..