【数据结构算法】判断一个树是否是另一个树的子结构

题目

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）

解题

# -*- coding:utf-8 -*-
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None
def isSame(pRoot1, pRoot2):
    if pRoot2 is None:
            return True
    elif pRoot2 is not None and pRoot1 is None:
            return False
    elif pRoot1.val ==pRoot2.val:
        return isSame(pRoot1.left,pRoot2.left) and isSame(pRoot1.right,pRoot2.right) 
    else:
        return False



class Solution:
    
    @staticmethod
    def HasSubtree(pRoot1, pRoot2):
        def solu(pRoot1, pRoot2):
            # write code here
            if pRoot2 is None:
                return False
            elif pRoot2 is not None and pRoot1 is None:
                return False
            elif pRoot1.val == pRoot2.val and isSame(pRoot1,pRoot2):
                 return True
            else:
                return solu(pRoot1.left, pRoot2) or solu(pRoot1.right, pRoot2)
            
        return solu(pRoot1, pRoot2)