B. World Tour 题目连接: http://www.codeforces.com/contest/666/problem/B Description A famous sculptor Cicasso goes to a world tour! Well, it is not actually a world-wide. But not everyone should have the opportunity to see works of sculptor, shouldn't he…

D. World Tour   A famous sculptor Cicasso goes to a world tour! Well, it is not actually a world-wide. But not everyone should have the opportunity to see works of sculptor, shouldn't he? Otherwise there will be no any exclusivity. So Cicasso will en…

题目链接: http://www.codeforces.com/contest/666/problem/B 题意: 给你n个城市,m条单向边,求通过最短路径访问四个不同的点能获得的最大距离,答案输出一个满足条件的四个点. 题解: 首先预处理出任意两点的最短距离,用队列优化的spfa跑:O(n*n*logn) 现依次访问四个点:v1,v2,v3,v4 我们可以枚举v2,v3,然后求出v2的最远点v1,v3的最远点v4,为了保证这四个点的不同,直接用最远点会错,v1,v4相同时还要考虑次最远点来替换…

题目链接:http://codeforces.com/contest/667/problem/D 给你一个有向图,dis[i][j]表示i到j的最短路,让你求dis[u][i] + dis[i][j] + dis[j][v]的最大值,其中u i j v互不相同. 先用优先队列的dijkstra预处理出i到j的最短距离(n^2 logn).(spfa也可以做) 然后枚举4个点的中间两个点i j,然后枚举与i相连节点的最短路dis[u][i](只要枚举最长的3个就行了),接着枚举与j相连节点的最短路…

A. Reberland Linguistics 题目连接: http://www.codeforces.com/contest/666/problem/A Description First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The educati…

题目链接: 题目 A. Reberland Linguistics time limit per test:1 second memory limit per test:256 megabytes 问题描述 First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university…

C. Reberland Linguistics time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talent…

题意:给一个初始串s,和m个模式串,q次查询每次问你第l到第r个模式串中包含\(s_l-s_r\)子串的最大数量是多少 题解:把初始串和模式串用分隔符间隔然后建sam,我们需要找到在sam中表示\(s_l-s_r\)子串的状态节点(先找到\(s_r\)对应的节点,然后倍增parent树即可),我们需要找到包含\(s_l-s_r\)的模式串,这些节点肯定在parent树上位于我们找到的状态节点的子树上.那么我们按sam的topo序进行线段树合并,线段树区间表示l,r模式串中最大匹配值以及下标.每次…

第一题直接算就行了为了追求手速忘了输出yes导致wa了一发... 第二题技巧题,直接sort,然后把最大的和其他的相减就是构成一条直线,为了满足条件就+1 #include<map> #include<set> #include<cmath> #include<queue> #include<stack> #include<vector> #include<cstdio> #include<iomanip> #…

C. Reberland Linguistics     First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge…

题目链接: http://codeforces.com/contest/672/problem/C 题意: 公园里有两个人一个垃圾桶和n个瓶子,现在这两个人需要把所有的瓶子扔进垃圾桶,给出人,垃圾桶,瓶子的坐标,问两个人需要走的最短距离和. 题解: 首先必须要有一个人先去检一个瓶子,然后走到垃圾桶,这个可以枚举,接下来就是考虑另一个人是也捡一个瓶子然后走到垃圾桶(这个可以预处理出最优的,和次优的,因为如果最优的那个刚好被第一个人拿走了,那就拿次优的)还是在原地不动,接下去就是固定的了,求剩下的所…

C. Watering Flowers 题目连接: http://www.codeforces.com/contest/617/problem/C Descriptionww.co A flowerbed has many flowers and two fountains. You can adjust the water pressure and set any values r1(r1 ≥ 0) and r2(r2 ≥ 0), giving the distances at which t…

题目链接: http://codeforces.com/contest/567/problem/E 题意: 给你一个带重边的图,求三类边: 在最短路构成的DAG图中,哪些边是必须经过的: 其他的(包括不在DAG上的边)不是必须经过的边把权值改小多少才能通过, 或者根本不可能通过的. 题解: 从起点s跑一遍最短路得到d[maxn],从终点t跑一遍最短路得到d2[maxn],对于边(u,v,w),如果d[u]+d2[v]+w==d[t]那么这条边在最短路上,对于不在最短路上的边,如果d[u]+d2[…

题目链接:http://codeforces.com/problemset/problem/686/C 给你n和m,问你有多少对(a, b) 满足0<=a <n 且 0 <=b < m 且a的7进制和n-1的7进制位数相同 且b的7进制和m-1的7进制位数相同,还有a和b的7进制上的每位上的数各不相同. 看懂题目,就很简单了,先判断a和b的7进制位数是否超过7,不超过的话就dfs暴力枚举计算就可以了. //#pragma comment(linker, "/STACK:1…

B. Biridian Forest Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/329/problem/B Description You're a mikemon breeder currently in the middle of your journey to become a mikemon master. Your current obstacle is go through t…

D. Valid Sets Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/486/problem/D Description As you know, an undirected connected graph with n nodes and n - 1 edges is called a tree. You are given an integer d and a tree consist…

B. Once Again... Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/582/problem/B Description You are given an array of positive integers a1, a2, ..., an × T of length n × T. We know that for any i > n it is true that ai = ai -…

C. GCD Table Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/583/problem/C Description The GCD table G of size n × n for an array of positive integers a of length n is defined by formula Let us remind you that the greatest c…

D. Three Logos Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/581/problem/D Description Three companies decided to order a billboard with pictures of their logos. A billboard is a big square board. A logo of each company is…

B. Two Sets Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/468/problem/B Description Little X has n distinct integers: p1, p2, ..., pn. He wants to divide all of them into two sets A and B. The following two conditions must…

题目链接: http://codeforces.com/problemset/problem/301/B B. Yaroslav and Time time limit per test2 secondsmemory limit per test256 megabytes 问题描述 Yaroslav is playing a game called "Time". The game has a timer showing the lifespan he's got left. As s…

A. Robbers' watch 题目连接: http://www.codeforces.com/contest/685/problem/A Description Robbers, who attacked the Gerda's cab, are very successful in covering from the kingdom police. To make the goal of catching them even harder, they use their own watc…

A. Help Farmer 题目连接: http://www.codeforces.com/contest/142/problem/A Description Once upon a time in the Kingdom of Far Far Away lived Sam the Farmer. Sam had a cow named Dawn and he was deeply attached to her. Sam would spend the whole summer stocki…

A. Recycling Bottles 题目连接: http://www.codeforces.com/contest/671/problem/A Description It was recycling day in Kekoland. To celebrate it Adil and Bera went to Central Perk where they can take bottles from the ground and put them into a recycling bin.…

C. Removing Columns time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given an n × m rectangular table consisting of lower case English letters. In one operation you can completely r…

A. Combination Lock Time Limit: 1 Sec  Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/540/problem/A Description Scrooge McDuck keeps his most treasured savings in a home safe with a combination lock. Each time he wants to put there the treas…

D. Image Preview 题目连接: http://www.codeforces.com/contest/651/problem/D Description Vasya's telephone contains n photos. Photo number 1 is currently opened on the phone. It is allowed to move left and right to the adjacent photo by swiping finger over…

B. Beautiful Paintings 题目连接: http://www.codeforces.com/contest/651/problem/B Description There are n pictures delivered for the new exhibition. The i-th painting has beauty ai. We know that a visitor becomes happy every time he passes from a painting…

A. Minimum Difficulty time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Mike is trying rock climbing but he is awful at it. There are n holds on the wall, i-th hold is at height ai off the g…

A. Hongcow Learns the Cyclic Shift time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Hongcow is learning to spell! One day, his teacher gives him a word that he needs to learn to spell. Bein…