MAYBE

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

Strict Trs:
  { rev(ls) -> r1(ls, empty())
  , r1(empty(), a) -> a
  , r1(cons(x, k), a) -> r1(k, cons(x, a)) }
Obligation:
  innermost runtime complexity
Answer:
  MAYBE

The input cannot be shown compatible

Arrrr..