剑指Offer 26 树的子结构

输入两棵二叉树A，B，判断B是不是A的子结构。（ps：我们约定空树不是任意一个树的子结构）

 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     def isSubWithRoot(self,pRoot1,pRoot2):
 9         if pRoot2 == None:
10             return True
11         if pRoot1 == None:
12             return False
13         if pRoot1.val != pRoot2.val:
14             return False
15         return self.isSubWithRoot(pRoot1.left,pRoot2.left) and self.isSubWithRoot(pRoot1.right,pRoot2.right)
16     
17     def HasSubtree(self, pRoot1, pRoot2):
18         if pRoot1 == None or pRoot2 == None:
19             return False
20         return self.isSubWithRoot(pRoot1,pRoot2) or self.HasSubtree(pRoot1.left,pRoot2) or self.HasSubtree(pRoot1.right,pRoot2)
21         # write code here