MAYBE

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

Strict Trs:
  { check(0()) -> zero()
  , check(s(0())) -> odd()
  , check(s(s(0()))) -> even()
  , check(s(s(s(x)))) -> check(s(x))
  , half(0()) -> 0()
  , half(s(0())) -> 0()
  , half(s(s(x))) -> s(half(x))
  , plus(0(), y) -> y
  , plus(s(x), y) -> s(plus(x, y))
  , times(x, y) -> timesIter(x, y, 0())
  , timesIter(x, y, z) -> if(check(x), x, y, z, plus(z, y))
  , if(zero(), x, y, z, u) -> z
  , if(odd(), x, y, z, u) -> timesIter(p(x), y, u)
  , if(even(), x, y, z, u) ->
    plus(timesIter(half(x), y, half(z)),
         timesIter(half(x), y, half(s(z))))
  , p(0()) -> 0()
  , p(s(x)) -> x }
Obligation:
  innermost runtime complexity
Answer:
  MAYBE

The input cannot be shown compatible

Arrrr..