Invert Binary Tree
Description
Given the root
of a binary tree, invert the tree, and return its root.
Example 1:
![](https://assets.leetcode.com/uploads/2021/03/14/invert1-tree.jpg)
Input: root = [4,2,7,1,3,6,9] Output: [4,7,2,9,6,3,1]
Example 2:
![](https://assets.leetcode.com/uploads/2021/03/14/invert2-tree.jpg)
Input: root = [2,1,3] Output: [2,3,1]
Example 3:
Input: root = [] Output: []
Constraints:
- The number of nodes in the tree is in the range
[0, 100]
. -100 <= Node.val <= 100
Solution(javascript)
/**
* Definition for a binary tree node.
* function TreeNode(val, left, right) {
* this.val = (val===undefined ? 0 : val)
* this.left = (left===undefined ? null : left)
* this.right = (right===undefined ? null : right)
* }
*/
/**
* @param {TreeNode} root
* @return {TreeNode}
*/
var invertTree = function(root) {
if (root == null) return root;
[root.left, root.right] = [invertTree(root.right), invertTree(root.left)];
return root;
};