原题链接在这里:https://leetcode.com/problems/keys-and-rooms/ 题目: There are N rooms and you start in room 0.  Each room has a distinct number in 0, 1, 2, ..., N-1, and each room may have some keys to access the next room. Formally, each room i has a list of…

There are N rooms and you start in room 0.  Each room has a distinct number in 0, 1, 2, ..., N-1, and each room may have some keys to access the next room. Formally, each room i has a list of keys rooms[i], and each key rooms[i][j] is an integer in […

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 DFS BFS 日期 题目地址:https://leetcode.com/problems/keys-and-rooms/description/ 题目描述 There are N rooms and you start in room 0. Each room has a distinct number in 0, 1, 2, -, N-1, an…

题目链接:https://leetcode.com/problems/keys-and-rooms/description/ 简单DFS time:9ms 1 class Solution { 2 public: 3 void DFS(int root,vector<int>& visited,vector<vector<int>>& rooms){ 4 visited[root] = 1; 5 for(auto x : rooms[root]){ 6…

题目: ​ 有 N 个房间,开始时你位于 0 号房间.每个房间有不同的号码:0,1,2,...,N-1,并且房间里可能有一些钥匙能使你进入下一个房间. ​ 在形式上,对于每个房间 i 都有一个钥匙列表 rooms[i],每个钥匙 rooms[i][j] 由 [0,1,...,N-1] 中的一个整数表示,其中 N = rooms.length. 钥匙 rooms[i][j] = v 可以打开编号为 v 的房间. 最初,除 0 号房间外的其余所有房间都被锁住. 你可以自由地在房间之间来回走动. 如果…

There are N rooms and you start in room 0.  Each room has a distinct number in 0, 1, 2, ..., N-1, and each room may have some keys to access the next room. Formally, each room i has a list of keys rooms[i], and each key rooms[i][j] is an integer in […

1.题目描述 2.问题分析 使用深度优先遍历 3.代码 bool canVisitAllRooms(vector<vector<int>>& rooms) { int nums = rooms.size(); ) return true; vector<); R[] = ; stack<int> s; s.push(); while (!s.empty()) { int room = s.top(); s.pop(); for(auto n : rooms…

There are N rooms and you start in room 0.  Each room has a distinct number in 0, 1, 2, ..., N-1, and each room may have some keys to access the next room. Formally, each room i has a list of keys rooms[i], and each key rooms[i][j] is an integer in […

Imagine you have a special keyboard with the following keys: Key 1: (A): Print one 'A' on screen. Key 2: (Ctrl-A): Select the whole screen. Key 3: (Ctrl-C): Copy selection to buffer. Key 4: (Ctrl-V): Print buffer on screen appending it after what has…

Initially on a notepad only one character 'A' is present. You can perform two operations on this notepad for each step: Copy All: You can copy all the characters present on the notepad (partial copy is not allowed). Paste: You can paste the character…

原题链接在这里:https://leetcode.com/problems/4-keys-keyboard/description/ 题目: Imagine you have a special keyboard with the following keys: Key 1: (A): Print one 'A' on screen. Key 2: (Ctrl-A): Select the whole screen. Key 3: (Ctrl-C): Copy selection to buff…

""" There are N rooms and you start in room 0. Each room has a distinct number in 0, 1, 2, ..., N-1, and each room may have some keys to access the next room. Formally, each room i has a list of keys rooms[i], and each key rooms[i][j] is an…

1. 2 Keys Keyboard 先把dp的最小不走都设置为无穷大(Integer.MAX_VALUE),初始化条件:dp[0] = dp[1] = 0,状态转移方程为dp[i] = Math.min( dp[i] , dp[j] + i / j ), 1 < i < n + 1 , 1 <= j < i,且i是j的整数倍上述状态转移方程表示:如果i是j的倍数,那么i可以通过粘贴(i/j-1)次j得到,再加上一次复制操作,那么可以通过dp[j]+i/j次操作得到dp[i].…

作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 排序+堆 日期 题目地址:https://leetcode-cn.com/problems/meeting-rooms/ 题目描述 Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), fin…

作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 排序 日期 题目地址:https://leetcode-cn.com/problems/meeting-rooms/ 题目描述 Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), deter…

All LeetCode Questions List(Part of Answers, still updating) 题目汇总及部分答案(持续更新中) Leetcode problems classified by company 题目按公司分类(Last updated: October 2, 2017) .   Top Interview Questions # Title Difficulty Acceptance 1 Two Sum Medium 17.70% 2 Add Two N…

DFS基础 深度优先搜索(Depth First Search)是一种搜索思路,相比广度优先搜索(BFS),DFS对每一个分枝路径深入到不能再深入为止,其应用于树/图的遍历.嵌套关系处理.回溯等,可以用递归.堆栈(stack)实现DFS过程. 关于广度优先搜索(BFS)详见:算法与数据结构基础 - 广度优先搜索(BFS) 关于递归(Recursion)详见:算法与数据结构基础 - 递归(Recursion) 树的遍历 DFS常用于二叉树的遍历,关于二叉树详见: 算法与数据结构基础 - 二叉查找树…

请点击页面左上角 -> Fork me on Github 或直接访问本项目Github地址:LeetCode Solution by Swift    说明:题目中含有$符号则为付费题目. 如:[Swift]LeetCode156.二叉树的上下颠倒 $ Binary Tree Upside Down 请下拉滚动条查看最新 Weekly Contest!!! Swift LeetCode 目录 | Catalog 序        号 题名Title 难度     Difficulty  两数之…

Contest 81 (2018年11月8日,周四,凌晨) 链接:https://leetcode.com/contest/weekly-contest-81 比赛情况记录:结果:3/4, ranking: 440/2797.这次题目似乎比较简单,因为我比赛的时候前三题全做出来了(1:12:39),然后第四题有思路,正在写,没写完,比赛完了写完提交也对了. [821]Shortest Distance to a Character(第一题 4分) 给了一个单词(字符串)s,和单词中的任意一个字母…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 把自己刷过的所有题目做一个整理,并且用简洁的语言概括了一下思路,汇总成了一个表格. 题目的排列顺序是按照先Easy再Medium再Hard排列的,暂时还没有把题目全部整理完成.后序我会把刷过的所有的题目都整理到这个文档里. 题目 难度 解法 题目地址 566. Reshape the Matrix Easy 变长数组,求余法,维护行列计算在新的数组中的位置 https://blog.c…

[98]Validate Binary Search Tree [99]Recover Binary Search Tree [100]Same Tree [101]Symmetric Tree [104]Maximum Depth of Binary Tree [105]Construct Binary Tree from Preorder and Inorder Traversal [106]Construct Binary Tree from Inorder and Postorder T…

[133]Clone Graph (2019年3月9日,复习) 给定一个图,返回它的深拷贝. 题解:dfs 或者 bfs 都可以 /* // Definition for a Node. class Node { public: int val; vector<Node*> neighbors; Node() {} Node(int _val, vector<Node*> _neighbors) { val = _val; neighbors = _neighbors; } };…

项目地址 服务器源码地址:https://github.com/ermu592275254/chat-socket 网页源码地址:https://github.com/ermu592275254/chat-socket 项目设计概述 相关技术 nodejs 使用nodejs搭建后台,因为是一个单页应用,并且前后端通信使用了webSocket,所有只用http模块搭建一个简单的服务器,未使用koa.express等web框架. webSocket 使用socket.io实现webSocket,前端…

Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), find the minimum number of conference rooms required. For example,Given [[0, 30],[5, 10],[15, 20]],return 2. 这道题是之前那道Meeting Rooms的拓展,那道题只让我们是…

Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), determine if a person could attend all meetings. For example,Given [[0, 30],[5, 10],[15, 20]],return false. 这道题给了我们一堆会议的时间,问我们能不能同时参见所有的会议,这实际…

原题链接在这里:https://leetcode.com/problems/meeting-rooms-ii/ Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), find the minimum number of conference rooms required. For example,Given [[0, 30],[5, 1…

原题链接在这里:https://leetcode.com/problems/meeting-rooms/ Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), determine if a person could attend all meetings. For example,Given [[0, 30],[5, 10],[15,…

1. Longest Palindromic Substring Given a string s, find the longest palindromic substring in s. You may assume that the maximum length of s is 1000. Example: Input: "babad" Output: "bab" Note: "aba" is also a valid answer. Ex…

We are given a 2-dimensional grid. "." is an empty cell, "#" is a wall, "@" is the starting point, ("a", "b", ...) are keys, and ("A", "B", ...) are locks. We start at the starting poin…

Initially on a notepad only one character 'A' is present. You can perform two operations on this notepad for each step: Copy All: You can copy all the characters present on the notepad (partial copy is not allowed). Paste: You can paste the character…