package example

case class Tree(val value: Int, val childs: List[Tree])

object DeepestNode extends App {

  def findDeepestNode(tree: Tree): Tree = {
    def loop(subtree: Tree, acc: (Int, Tree)): (Int, Tree) =
      subtree.childs match {
        case x: List[Tree] => {
          (for (t <- x)
            yield acc._1 -> loop(t, (acc._1 + 1, t))
          ).maxBy(_._1)._2
        }
        case _ => acc
      }

    loop(tree, (0, tree))._2
  }

  val tree = Tree(1, List(Tree(2, null)))
  println(findDeepestNode(tree).value)

}