B. Photo to Remember Time Limit: 1 Sec  Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/522/problem/B Description One day n friends met at a party, they hadn't seen each other for a long time and so they decided to make a group photo together…

D. Closest Equals Time Limit: 1 Sec  Memory Limit: 256 MB 题目连接 http://www.lydsy.com/JudgeOnline/problem.php?id=3224 Description You are given sequence a1, a2, ..., an and m queries lj, rj (1 ≤ lj ≤ rj ≤ n). For each query you need to print the minimu…

题目链接: http://codeforces.com/problemset/problem/522/D D. Closest Equals time limit per test3 secondsmemory limit per test256 megabytes 问题描述 You are given sequence a1, a2, ..., an and m queries lj, rj (1 ≤ lj ≤ rj ≤ n). For each query you need to print…

传送门 A. Reposts time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output One day Polycarp published a funny picture in a social network making a poll about the color of his handle. Many of his friend…

题目地址:http://blog.csdn.net/shiyuankongbu/article/details/10004443 /* 题意:在i前面找回文子串,在i后面找回文子串相互配对,问有几对 DP:很巧妙的从i出发向两头扩展判断是否相同来找回文串 dpr[i] 代表记录从0到i间的回文子串的个数,dpl[i] 代表记录i之后的回文子串个数 两两相乘就行了 详细解释:http://blog.csdn.net/shiyuankongbu/article/details/10004443 */…

A. Home Numbers 题目连接: http://www.codeforces.com/contest/638/problem/A Description The main street of Berland is a straight line with n houses built along it (n is an even number). The houses are located at both sides of the street. The houses with od…

题目链接:http://codeforces.com/contest/522/problem/D 题目大意:  给你一个长度为n的序列,然后有m次查询,每次查询输入一个区间[li,lj],对于每一个查询,输出在这个区间内的两个相等的数的最短距离,如果没有相等的则输出-1. 线段树+扫描线,线段树维护的值是区间的最小值,从后往前扫,然后每次要做的事有两个: 1.判断当前这个位置 i 的数刚刚是不是出现过,假设刚刚出现的位置是 l ,如果出现过,则在线段树中把l这个位置的值更新为 l - i,同时更…

C. Cd and pwd commands Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/problemset/problem/158/C Description Vasya is writing an operating system shell, and it should have commands for working with directories. To begin with, he dec…

C. String Manipulation 1.0 Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 codeforces.com/problemset/problem/91/B Description One popular website developed an unusual username editing procedure. One can change the username only by deleting some characte…

今天在codeforces上面做到一道题:http://codeforces.com/contest/638/problem/B 题目大意是:给定n个字符串,找到最短的字符串S使得n个字符串都是这个字符串S的子串. 题目里有一个限制条件是每个字母都最多出现一次,所以可以用下面的方法来解决: http://codeforces.com/contest/638/submission/16900955 然后我想到如果问题没有“每个字母最多只出现一次”这个限制的话应该怎么解决. 暂时还在想………