|
| 1 | +/* |
| 2 | + * @lc app=leetcode.cn id=226 lang=java |
| 3 | + * |
| 4 | + * [226] 翻转二叉树 |
| 5 | + * |
| 6 | + * https://leetcode-cn.com/problems/invert-binary-tree/description/ |
| 7 | + * |
| 8 | + * algorithms |
| 9 | + * Easy (75.17%) |
| 10 | + * Likes: 462 |
| 11 | + * Dislikes: 0 |
| 12 | + * Total Accepted: 83.9K |
| 13 | + * Total Submissions: 111.4K |
| 14 | + * Testcase Example: '[4,2,7,1,3,6,9]' |
| 15 | + * |
| 16 | + * 翻转一棵二叉树。 |
| 17 | + * |
| 18 | + * 示例: |
| 19 | + * |
| 20 | + * 输入: |
| 21 | + * |
| 22 | + * 4 |
| 23 | + * / \ |
| 24 | + * 2 7 |
| 25 | + * / \ / \ |
| 26 | + * 1 3 6 9 |
| 27 | + * |
| 28 | + * 输出: |
| 29 | + * |
| 30 | + * 4 |
| 31 | + * / \ |
| 32 | + * 7 2 |
| 33 | + * / \ / \ |
| 34 | + * 9 6 3 1 |
| 35 | + * |
| 36 | + * 备注: |
| 37 | + * 这个问题是受到 Max Howell 的 原问题 启发的 : |
| 38 | + * |
| 39 | + * 谷歌:我们90%的工程师使用您编写的软件(Homebrew),但是您却无法在面试时在白板上写出翻转二叉树这道题,这太糟糕了。 |
| 40 | + * |
| 41 | + */ |
| 42 | + |
| 43 | +// @lc code=start |
| 44 | +/** |
| 45 | + * Definition for a binary tree node. |
| 46 | + * public class TreeNode { |
| 47 | + * int val; |
| 48 | + * TreeNode left; |
| 49 | + * TreeNode right; |
| 50 | + * TreeNode(int x) { val = x; } |
| 51 | + * } |
| 52 | + */ |
| 53 | +class Solution { |
| 54 | + public TreeNode invertTree(TreeNode root) { |
| 55 | + if (root == null) { |
| 56 | + return root; |
| 57 | + } |
| 58 | + TreeNode left = invertTree(root.right); |
| 59 | + TreeNode right = invertTree(root.left); |
| 60 | + root.left = left; |
| 61 | + root.right = right; |
| 62 | + return root; |
| 63 | + } |
| 64 | +} |
| 65 | +// @lc code=end |
| 66 | + |
0 commit comments