[리트코드] 226. Invert Binary Tree - js

1. 문제

https://leetcode.com/problems/invert-binary-tree/description/

Invert Binary Tree - LeetCode

2. 코드

/**
 * 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;
    // 자식 노드부터 순서 바꾸고 올라오는 재귀 형태
    invertTree(root.left);
    invertTree(root.right);

    const cur = root.left;
    root.left = root.right;
    root.right = cur;

    return root;
};

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