0226_Invert_Binary_Tree.java

/*
 * 226. Invert Binary Tree
 * Problem Link: https://leetcode.com/problems/invert-binary-tree/
 * Difficulty:   Easy
 * 
 * Solution Created by: Muhammad Khuzaima Umair
 * LeetCode : https://leetcode.com/mkhuzaima/
 * Github   : https://github.com/mkhuzaima
 * LinkedIn : https://www.linkedin.com/in/mkhuzaima/
 */
/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    public TreeNode invertTree(TreeNode root) {

        if (root == null) return root;

        TreeNode temp = root.left;

        root.left = invertTree(root.right);
        root.right = invertTree(temp);

        return root;     
    }
}