题目链接：https://leetcode-cn.com/problems/invert-binary-tree/
翻转一棵二叉树。
示例：
输入：
4
/
2 7
/ /
1 3 6 9
输出：
4
/
7 2
/ /
9 6 3 1
我写的：
1 /** 2 * Definition for a binary tree node. 3 * struct TreeNode { 4 * int val; 5 * struct TreeNode *left; 6 * struct TreeNode *right; 7 * }; 8 */ 9 struct TreeNode* invertTree(struct TreeNode* root){ 10 if(root==NULL) return root; 11 struct TreeNode *tmp=root->left; 12 root->left=root->right; 13 root->right=tmp; 14 root->left=invertTree(root->left); 15 root->right=invertTree(root->right); 16 return root; 17 }
官方解法：
1 struct TreeNode* invertTree(struct TreeNode* root){ 2 if(root==NULL) return root; 3 struct TreeNode *right = invertTree(root->right); 4 struct TreeNode *left = invertTree(root->left); 5 root->left = right; 6 root->right = left; 7 return root; 8 }