MAYBE

We are left with following problem, upon which TcT provides the
certificate MAYBE.

Strict Trs:
  { add(true(), x, xs) ->
    add(and(isNat(x), isList(xs)), x, Cons(x, xs))
  , and(x, false()) -> false()
  , and(true(), true()) -> true()
  , and(false(), x) -> false()
  , isNat(s(x)) -> isNat(x)
  , isNat(0()) -> true()
  , isList(Cons(x, xs)) -> isList(xs)
  , isList(nil()) -> true()
  , if(true(), x, y) -> x
  , if(false(), x, y) -> y }
Obligation:
  innermost runtime complexity
Answer:
  MAYBE

The input cannot be shown compatible

Arrrr..