TreeHeight.java

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 TreeHeight {
  /*
    class Node
    	int data;
    	Node left;
    	Node right;
	*/
	static int height(Node root) {
       int lcount=0, rcount=0;

        if(root==null){
            return -1;
        }
        else if(root.left == null && root.right==null){
            return 0;
        }
        else{
            lcount = height(root.left);
            rcount = height(root.right);
        }
        if(lcount > rcount){
            return lcount+1;
        }
    return rcount+1;
    }
    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;
        }
    }
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int t = scan.nextInt();
        Node root = null;
        while(t-- > 0){
            int data = scan.nextInt();
            root = insert(root, data);
        }
        scan.close();
        int height = height(root);
        System.out.println(height);
    }
}