leetcode 翻转二叉树 简单

 

 

没什么坑，在回溯的时候交换两儿子即可

class Solution {
public:
    TreeNode* invertTree(TreeNode* root) {
        if(root == nullptr) return nullptr;
        invertTree(root -> left);
        invertTree(root -> right);
        auto temp = root -> left;
        root -> left = root -> right;
        root -> right = temp;
        return root;
    }
};