TRS:
 {         plus(0(), x) -> x,
          plus(s(x), y) -> s(plus(p(s(x)), y)),
          times(0(), y) -> 0(),
         times(s(x), y) -> plus(y, times(p(s(x)), y)),
            exp(x, 0()) -> s(0()),
           exp(x, s(y)) -> times(x, exp(x, y)),
              p(s(0())) -> 0(),
             p(s(s(x))) -> s(p(s(x))),
            tower(x, y) -> towerIter(x, y, s(0())),
   towerIter(0(), y, z) -> z,
  towerIter(s(x), y, z) -> towerIter(p(s(x)), y, exp(y, z))}
 Fail