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