新月

Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 4646    Accepted Submission(s): 2345Problem DescriptionA school bought the first c

Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 327680/327680 K (Java/Others)Total Submission(s): 2524    Accepted Submission(s): 760Problem DescriptionGenghis Khan(成吉思汗)(1162-1

Time Limit: 6000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 6527    Accepted Submission(s): 3836Problem DescriptionACboy很喜欢玩一种战略游戏，在一个地图上，有N座城

Time Limit: 1000MS Memory Limit: 65536KTotal Submissions: 8672 Accepted: 2884DescriptionWshxzt is a lovely girl. She likes apple very much. One day HX takes her to an apple

题目链接：点击打开链接题意：给你一个n个点m条边的无向无环图，在尽量少的节点上放灯，使得所有边都被照亮，每盏灯将照亮以它为一个端点的所有边。在灯的总数最小的前提下，被两盏灯同时照亮的边数应尽量大。思路：无向无环图的另一个说法是“森林”，即由多棵树组成，我们可以先算一棵树上的答案，然后累加起来就行了。本题的优化目标有两个：放置的灯数应尽量少，被两盏灯照亮的边数b应尽量大。为了统一起见，我们把

Famil Door’s City map looks like a tree (undirected connected acyclic graph) so other people call it Treeland. There are n intersections in the city connected by n - 1 bidirectional roads.There

DescriptionPetar is throwing a birthday party and he decided to invite some of the employees of his company where he is the CEO. Each employee, including Petar, has a unique label from 1 to N, a

题目链接：点击打开链接题意：n台机器连成一个树状网络，其中叶节点是客户端，其他节点是服务器，目前有一台服务器s正在提供服务。让你在其他服务器上也安排同样的服务，使得每台客户端到最近服务器的距离不超过k，而且要使服务器尽量少，问最少要设置多少台服务器。思路：我们先把s看做根节点，做一遍dfs，把离s距离小于等于k的叶子节点标为访问过，表示这个叶子节点已经得到服务了，然后再把没有访问过的叶子节

You're given a matrix A of size n × n.Let's call the matrix with nonnegative elements magic if it is symmetric (so aij = aji), aii = 0 and aij ≤ max(aik, ajk) for all triples i, j, k. Note that 

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65768/65768 K (Java/Others)Total Submission(s): 2996    Accepted Submission(s): 1377Problem DescriptionHumans have discovered a ki

Time Limit: 1000MS Memory Limit: 30000KTotal Submissions: 10297 Accepted: 4701DescriptionThe cows have reconstructed Farmer John's farm, with its N barns (1 <= N <= 150, nu

Time Limit: 1000MS Memory Limit: 65536KTotal Submissions: 4314 Accepted: 2337DescriptionA TV-network plans to broadcast an important football match. Their network of transm

Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 14426    Accepted Submission(s): 3887Problem DescriptionYou, the leader of Starsh

time limit per test3 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard outputThe country Treeland consists of n cities, some pairs of them ar

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 7191    Accepted Submission(s): 3174Problem DescriptionThere is going to be a part

Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 242    Accepted Submission(s): 80Problem DescriptionThere was a civil war between