MAYBE
Trs:
 { cond(true(), x, y) -> s(minus(x, s(y))),
  cond(false(), x, y) -> 0(),
          minus(x, y) -> cond(ge(x, s(y)), x, y),
        ge(0(), s(v)) -> false(),
       ge(s(u), s(v)) -> ge(u, v),
           ge(u, 0()) -> true()}
 Comment:
  We consider a duplicating trs.
  FAIL:
   Open