Leetcode 114.二叉树展开为链表

二叉树展开为链表

给定一个二叉树，原地将它展开为链表。

例如，给定二叉树

1

/ \

2 5

/ \ \

3 4 6

将其展开为：

1

\

2

\

3

\

4

\

5

\

6

 1 class Solution{
 2 public:
 3     void flatten(TreeNode* root){
 4         if (root == NULL) return;
 5         flatten(root->left);
 6         flatten(root->right);
 7         TreeNode *temp = root->right;
 8         root->right = root->left;
 9         root->left = NULL;
10         while (root->right) root = root->right;
11         root->right = temp;
12     }
13 }