LeetCode 226. Invert Binary Tree

递归的思想

/** * Definition for a binary tree node. * struct TreeNode { * int val; * struct TreeNode *left; * struct TreeNode *right; * }; */
struct TreeNode* invertTree(struct TreeNode* root) {

    if(root==NULL)
        return NULL;
    else
    {
        struct TreeNode* temp = root->right;
        root->right = root->left;
        root->left = temp;
        invertTree(root->right);
        invertTree(root->left);
        return root;
    }

}