LeetCode 226. 翻转二叉树
原题链接
简单
作者:
caichuntao
,
2023-06-25 15:53:16
,
所有人可见
,
阅读 107
方法1:递归
时间复杂度:$O(n)$
空间复杂度:最差$O(n)$,平均$O(logn)$。
解题思路
https://leetcode.cn/problems/invert-binary-tree/solution/dong-hua-yan-shi-liang-chong-shi-xian-226-fan-zhua/
Java 代码
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode() {}
* TreeNode(int val) { this.val = val; }
* TreeNode(int val, TreeNode left, TreeNode right) {
* this.val = val;
* this.left = left;
* this.right = right;
* }
* }
*/
class Solution {
public TreeNode invertTree(TreeNode root) {
if (root == null) {
return root;
}
TreeNode tmp = root.right;
root.right = root.left;
root.left = tmp;
invertTree(root.left);
invertTree(root.right);
return root;
}
}