import java.util.*;
import java.io.*;

class Node {
    Node left;
    Node right;
    int data;

    Node(int data) {
        this.data = data;
        left = null;
        right = null;
    }
}

class Solution {

	/*
    class Node
    	int data;
    	Node left;
    	Node right;
	*/
	static int height=0;
    public static int height(Node root) {
        getHeight(root,0);
        return height;
    }

    public static void getHeight(Node root,int h){
        if(root!=null){
            if(root.left==null&&root.right==null){
                updateHeight(h);
            }
            else{
                getHeight(root.left,h+1);
                getHeight(root.right,h+1);
            }
        }
    }


    static void updateHeight(int h){
        if(h>height){
            height=h;
        }
    }
	public static Node insert(Node root, int data) {
        if(root == null) {
            return new Node(data);
        } else {
            Node cur;
            if(data <= root.data) {
                cur = insert(root.left, data);
                root.left = cur;
            } else {
                cur = insert(root.right, data);
                root.right = cur;
            }
            return root;
        }
    }