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