object Q3 extends App {

  object NumEnglishDicitionary {
    private val dictionary = Map(1 -> "one", 2 -> "two")
    /*
    def translate(num: Option[Int]): Option[String] = num match {
      case None    => None
      case Some(n) => dictionary.get(n)
    }
    */
    def translate(num: Option[Int]): Option[String] =
      num.fold(None: Option[String])(dictionary.get)
  }

  println(NumEnglishDicitionary.translate(Some(1)).contains("one"))
  println(NumEnglishDicitionary.translate(Some(3)).isEmpty)
  println(NumEnglishDicitionary.translate(None).isEmpty)
}