剑指offer——树的子结构
题目描述
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)
# -*- coding:utf-8 -*- # class TreeNode: # def __init__(self, x): # self.val = x # self.left = None # self.right = None class Solution: def isSubtree(self,pRoot1,pRoot2): if pRoot2==None: return True elif pRoot1==None or pRoot1.val!=pRoot2.val: return False return self.isSubtree(pRoot1.left,pRoot2.left) and self.isSubtree(pRoot1.right,pRoot2.right) def HasSubtree(self, pRoot1, pRoot2): # write code here if pRoot2==None or pRoot1==None: return False else: return self.isSubtree(pRoot1,pRoot2) or self.HasSubtree(pRoot1.left, pRoot2) or self.HasSubtree( pRoot1.right, pRoot2)