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…

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…

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> #…

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…

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…