[codeforces] 25E Test || hash】的更多相关文章

原题 给你三个字符串,找一个字符串(它的子串含有以上三个字符串),输出此字符串的长度. 先暴力判断是否有包含,消减需要匹配的串的数量.因为只有三个字符串,所以暴力枚举三个串的位置关系,对三个串跑好哈希,然后判断后缀与前缀重合长度即可. #include<cstdio> #include<algorithm> #include<cstring> #define mo 99994711 typedef long long ll; using namespace std; i…
Codeforces 25E Test E. Test Sometimes it is hard to prepare tests for programming problems. Now Bob is preparing tests to new problem about strings - input data to his problem is one string. Bob has 3 wrong solutions to this problem. The first gives…
题意 给出两个字符串\(s\)和\(t\),设\(S\)为\(s\)的任意一个非空前缀,\(T\)为\(t\)的任意一个非空前缀,问\(S+T\)有多少种不同的可能. Solution 看了一圈,感觉好像就我一个人写的\(kmp+hash+\)二分. 直接算好像不是很好算?先容斥一下,不同\(=\)总方案\(-\)相同. 显然总方案为两个字符串的长度的乘积,考虑相同的情况怎么算. 相同即两组\(S\)和\(T\)不同,但\(S+T\)本质相同的情况. 这个东西怎么算呢.... (感觉看图会好理解…
学了kmp之后又学了hash来搞字符串.这东西很巧妙,且听娓娓道来. 这题的题意是:一个字符串如果是回文的,那么k值加1,如果前一半的串也是回文,k值再加1,以此类推,算出其k值.打个比方abaaba,k值为3,abaxxaba,k值为1.现在,给出一个串,让你求这个串的所有前缀(包括本身)的k值的和. 如果考虑马拉车,那么先预处理出每个地方的最长回文长度,然后不断的截断,如果子串的回文长度大于其回文长度,那么k值加1,这样即可.但是马拉车写起来比较繁琐,没有模板我也没法手写. 这里提供hash…
Description Sometimes it is hard to prepare tests for programming problems. Now Bob is preparing tests to new problem about strings — input data to his problem is one string. Bob has 3 wrong solutions to this problem. The first gives the wrong answer…
题意 三个字符串,找一个字符串(它的子串含有以上三个字符串)使它的长度最短,输出此字符串的长度. 题解 先枚举字符串排列,直接KMP两两匹配,拼接即可...答案取最小值.. 常数巨大的丑陋代码 # include <stdio.h> # include <stdlib.h> # include <iostream> # include <string.h> # include <algorithm> using namespace std; #…
题目链接: http://codeforces.com/problemset/problem/155/E E. Double Profiles time limit per test 3 secondsmemory limit per test 256 megabytes 问题描述 You have been offered a job in a company developing a large social network. Your first task is connected wit…
C. Registration system Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/problemset/problem/4/C Description A new e-mail service "Berlandesk" is going to be opened in Berland in the near future. The site administration wants to…
E. Kefa and Watch Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/580/problem/E Description One day Kefa the parrot was walking down the street as he was on the way home from the restaurant when he saw something glittering b…
题目链接:https://codeforces.com/problemset/problem/1056/E One of Arkady's friends works at a huge radio telescope. A few decades ago the telescope has sent a signal $s$ towards a faraway galaxy. Recently they've received a response $t$ which they believe…