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