码迷,mamicode.com
首页 > 其他好文 > 详细

226. Invert Binary Tree

时间:2015-11-25 13:14:34      阅读:118      评论:0      收藏:0      [点我收藏+]

标签:

题目:

Invert a binary tree.

     4
   /     2     7
 / \   / 1   3 6   9

to

     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 fuck off.

链接: http://leetcode.com/problems/invert-binary-tree/ 

题解:

其实我还加这哥们LinkedIn了...后来他被Apple录取了,挺好的。 使用Recursive比较快就能写出来。

Time Complexity - O(n), Space Complexity - O(n)。

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
public class Solution {
    public TreeNode invertTree(TreeNode root) {
        if(root == null)
            return root;
        TreeNode left = root.left;
        root.left = invertTree(root.right);
        root.right = invertTree(left);
        
        return root;
    }
}

 

Reference:

https://leetcode.com/discuss/40001/straightforward-dfs-recursive-iterative-bfs-solutions

226. Invert Binary Tree

标签:

原文地址:http://www.cnblogs.com/yrbbest/p/4994276.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!