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Leetcode 226. 翻转二叉树

字数统计: 137阅读时长: 1 min
2020/09/16 Share

题目简介:

翻转一棵二叉树。

示例:

输入:

1
2
3
4
5
     4
/ \
2 7
/ \ / \
1 3 6 9

输出:

1
2
3
4
5
     4
/ \
7 2
/ \ / \
9 6 3 1

思路:

相当于中序遍历,从根节点出发,将左右子树互换即可。

代码如下:

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/**
* 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:

void dfs(TreeNode* root){

if(root == NULL)
return;

TreeNode* temp = root -> left;
root -> left = root -> right;
root -> right = temp;

dfs(root -> left);
dfs(root -> right);
}

TreeNode* invertTree(TreeNode* root) {

dfs(root);

return root;
}
};
CATALOG
  1. 1. 题目简介:
  2. 2. 思路:
  3. 3. 代码如下: