// x, f(x), f(f(x)), ..
    def riddleR(f : (Int) => Int, x : Int, num : Int, numanswers : Int) : Boolean =
     num match
     {
      case 0 =>
      {
       numanswers match
       {
        case 0 => readInt == x
        case _ if(numanswers >= 0) => readInt == x && riddleR(f, f(x), 0, numanswers - 1)
       }
      }
      case _ if(num > 0) =>
      {
       print(x + ", ")
       riddleR(f, f(x), num - 1, numanswers)
      }
     }