MAYBE

Problem:
 strict:
  times(x,0()) -> 0()
  times(x,s(y)) -> plus(times(x,y),x)
  plus(x,0()) -> x
  plus(0(),x) -> x
  plus(x,s(y)) -> s(plus(x,y))
  plus(s(x),y) -> s(plus(x,y))
 weak:
  rand(x) -> x
  rand(x) -> rand(s(x))

Proof:
 Open