using System;

using System.Collections.Generic;

public class Program

{

    public static Node deepestNode;

    public static int nodeLevel = 1;

    public static Node findNode(Node node)

    {

        Stack<Node> myStack = new Stack<Node>();

        if(node==null)

            return null;

        if (node!=null)

        {

            if(node.left !=null)

            {

                nodeLevel = nodeLevel +1;

                if( nodeLevel >

                deepestNode = node.left;

            }

            findNode(node.left);

            if (node.right!=null)

            {

               deepestNode = node.right;

               findNode(node.right);        

            }

        }

​

        return deepestNode;

    }

    public static void Main()

    {

        Node root = new Node(1);

        root.left = new Node(2);

        root.right = new Node(3);

        root.left.left = new Node(4);

        root.left.right = new Node(5);

        root.left.right.left = new Node(15);

        root.left.right.left =  new Node(19);

        root.right.left = new Node(6);

        root.right.right = new Node(7);

        root.right.right.left = new Node(8);

        root.right.right.left.right = new Node(11);

        var deepestNode = findNode(root);

        if(deepestNode!=null)

            Console.WriteLine("Deepest Node is " + deepestNode.data);

    }

}

​

public class Node {

    public int data;

    public Node left;

    public Node right;

​

    public Node(int data) {

        this.data = data;

    }

}