MAYBE We are left with following problem, upon which TcT provides the certificate MAYBE. Strict Trs: { f(0(x1)) -> s(0(x1)) , f(s(x1)) -> d(f(p(s(x1)))) , d(0(x1)) -> 0(x1) , d(s(x1)) -> s(s(d(p(s(x1))))) , p(s(x1)) -> x1 } Obligation: innermost runtime complexity Answer: MAYBE The input cannot be shown compatible Arrrr..