BinaryTree.scala

case class BinaryTree(info: String, left: Option[BinaryTree], right: Option[BinaryTree])

object Application extends App {

  val firstLeftFirstLeft = BinaryTree("firstLeftFirstLeft", None, None)
  val firstLeftFirstRight = BinaryTree("firstLeftFirstRight", None, None)

  val firstRightFirstLeft = BinaryTree("firstRightFirstLeft", None, None)

  val firstLeft = BinaryTree("firstLeft", Some(firstLeftFirstLeft), Some(firstLeftFirstRight))
  val firstRight = BinaryTree("firstRight", Some(firstRightFirstLeft), None)

  val rootNode = BinaryTree("rootNode", Some(firstLeft), Some(firstRight))


  def countNode(rootNode: BinaryTree) = {
    def countNodeReccur(rootNode: BinaryTree): Int = rootNode match {
      case BinaryTree(name, Some(left), Some(right)) =>
        1 + countNodeReccur(left) + countNodeReccur(right)
      case BinaryTree(name, None, Some(right)) =>
        1 + countNodeReccur(right)
      case BinaryTree(name, Some(left), None) =>
        countNodeReccur(left) + 1
      case BinaryTree(name, None, None) =>
        1
    }

    countNodeReccur(rootNode)
  }


  val count = countNode(rootNode)

  println("My Count " + count)

}