剑指Offer 27 二叉树的镜像

操作给定的二叉树，将其变换为源二叉树的镜像。

 1 # -*- coding:utf-8 -*-
 2 # class TreeNode:
 3 #     def __init__(self, x):
 4 #         self.val = x
 5 #         self.left = None
 6 #         self.right = None
 7 class Solution:
 8     # 返回镜像树的根节点
 9     def Mirror(self, root):
10         if root == None:
11             return None
12         if root.left != None and root.right != None:
13             temp = TreeNode(root.val)
14             temp.left = root.left
15             root.left = self.Mirror(root.right)
16             root.right = self.Mirror(temp.left)
17         elif root.left == None and root.right != None:
18             root.left = self.Mirror(root.right)
19             root.right = None
20         elif root.right == None and root.left != None:
21             root.right = self.Mirror(root.left)
22             root.left = None
23         return root
24         # write code here