object Main extends App {

  val age = io.StdIn.readLine.toInt

  val out = age match {
    case 1 => "Hello World"
    case 2 => {
      val A = io.StdIn.readLine.toInt
      val B = io.StdIn.readLine.toInt
      (A + B).toString
    }
  }

  println(out)
}
