LeetCode | 0100. Same Tree 相同的树【Python】
LeetCode 0100. Same Tree 相同的树【Easy】【Python】【二叉树】
Problem
Given two binary trees, write a function to check if they are the same or not.
Two binary trees are considered the same if they are structurally identical and the nodes have the same value.
Example 1:
Input: 1 1
/ \ / \
2 3 2 3
[1,2,3], [1,2,3]
Output: true
Example 2:
Input: 1 1
/ \
2 2
[1,2], [1,null,2]
Output: false
Example 3:
Input: 1 1
/ \ / \
2 1 1 2
[1,2,1], [1,1,2]
Output: false
问题
给定两个二叉树,编写一个函数来检验它们是否相同。
如果两个树在结构上相同,并且节点具有相同的值,则认为它们是相同的。
示例 1:
输入: 1 1
/ \ / \
2 3 2 3
[1,2,3], [1,2,3]
输出: true
示例 2:
输入: 1 1
/ \
2 2
[1,2], [1,null,2]
输出: false
示例 3:
输入: 1 1
/ \ / \
2 1 1 2
[1,2,1], [1,1,2]
输出: false
思路
二叉树
Python3代码
# Definition for a binary tree node.
# class TreeNode:
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
class Solution:
def isSameTree(self, p: TreeNode, q: TreeNode) -> bool:
# 两棵树都为空
if not p and not q:
return True
# 一棵树为空,另一棵不为空
elif not p or not q:
return False
# 两棵树都非空,但节点值不同
elif p.val != q.val:
return False
# 分别判断左子树和右子树
return self.isSameTree(p.left, q.left) and self.isSameTree(p.right, q.right)
GitHub链接
最怕一生碌碌无为,还说平凡难能可贵。