using System;

​

public class Program

{

    public Node root;

    public class Node

    {

        public int data;

        public Node left, right;

        public Node(int d)

        {

            data = d;

            left = right = null;

        }

    }

​

    public int getheight(Node node)

    {

        if (node == null)

            return 0;

        else

        {

            int lDepth = getheight(node.left);

            int rDepth = getheight(node.right);

            if (lDepth > rDepth)

                return (lDepth + 1);

            else

                return (rDepth + 1);

        }

    }

​

    public static void Main()

    {

        Program P = new Program();

        Node tnode = new Node(1);

        tnode.left = new Node(2);

        tnode.right = new Node(3);

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

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

        tnode.left.right.right = new Node(9);

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

        tnode.right.left.left = new Node(7);

        int height = P.getheight(tnode);

        Console.WriteLine(height);

    }

}