【Leetcode】之Symmetric Tree
来源:互联网 发布:mac怎么删除文件夹 编辑:程序博客网 时间:2024/06/06 02:32
一.问题描述
Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).
For example, this binary tree [1,2,2,3,4,4,3]
is symmetric:
1 / \ 2 2 / \ / \3 4 4 3
But the following [1,2,2,null,3,null,3]
is not:
1 / \ 2 2 \ \ 3 3
二.我的解题思路
如果一个二叉树是中心对称的,那么它左孩子的右子树一定是等他它右孩子的左子树,同理反过来亦然。所以直接使用判断两棵树是否相等的程序,测试通过的程序如下:
/** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */class Solution {public: bool isSymmetric(TreeNode* root) { if(!root) return true; int res = isEqual(root->left,root->right); return res; } bool isEqual(TreeNode* n1, TreeNode* n2){ if(!n1 && !n2) return true; if((!n2 && n1) || (!n1 && n2)) return false; if(n1->val!=n2->val) return false; else return isEqual(n1->left,n2->right) && isEqual(n1->right,n2->left); }};
0 0
- LeetCode 之 Symmetric Tree
- LeetCode之Symmetric Tree
- LeetCode之Symmetric Tree
- LeetCode之Symmetric Tree
- LeetCode 之 Symmetric Tree
- leetcode之Symmetric Tree
- leetcode之 Symmetric Tree
- leetcode之Symmetric Tree
- 【Leetcode】之Symmetric Tree
- LeetCode之 Symmetric Tree
- leetcode 之 Symmetric Tree 镜像树
- Leetcode - Tree - Symmetric Tree
- Leetcode - Tree - Symmetric Tree
- LeetCode[Tree]: Symmetric Tree
- [leetcode][tree] Symmetric Tree
- LeetCode: Symmetric Tree
- [Leetcode] Symmetric Tree
- LeetCode : Symmetric Tree
- Activity启动清空原任务栈
- javaScript笔记(十) 基本包装类型
- 安卓开发之封装显示倒计时按钮控件
- MP4(三)-复用器,数据的存储
- java源码:HashMap实现原理
- 【Leetcode】之Symmetric Tree
- PAT (Basic Level) Practise-1041
- 详细解析RxAndroid的使用方式
- Android关于R文件全部爆红的原因
- MP4(二)-解复用器
- Go语言学习笔记1/2
- Linux网络--主机DNS配置
- BMP图像处理
- HDU-2014