LeetCode 0226 - Invert Binary Tree

Reck Zhang

发布于 2021-08-11 12:13:16

2310

发布于 2021-08-11 12:13:16

文章被收录于专栏：Reck Zhang

Invert Binary Tree

Desicription

Invert a binary tree.

Example:

Input:

     4
   /   \
  2     7
 / \   / \
1   3 6   9

Output:

     4
   /   \
  7     2
 / \   / \
9   6 3   1

Trivia:

This problem was inspired by this original tweet by Max Howell:

Google: 90% of our engineers use the software you wrote (Homebrew), but you can’t invert a binary tree on a whiteboard so f*** off.

Solution

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    TreeNode* invertTree(TreeNode* root) {
        if(root == nullptr) {
            return nullptr;
        }
        auto left_node = invertTree(root->left);
        auto right_node = invertTree(root->right);
        root->left = right_node;
        root->right = left_node;
        return root;
    }
};

本文参与腾讯云自媒体同步曝光计划，分享自作者个人站点/博客。

原始发表：2018-07-05，如有侵权请联系 cloudcommunity@tencent.com 删除

binary