B. Rebranding   The name of one small but proud corporation consists of n lowercase English letters. The Corporation has decided to try rebranding — an active marketing strategy, that includes a set of measures to change either the brand (both for th…

B. Rebranding Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/591/problem/B Description The name of one small but proud corporation consists of n lowercase English letters. The Corporation has decided to try rebranding — an…

B. Rebranding The name of one small but proud corporation consists of n lowercase English letters. The Corporation has decided to try rebranding — an active marketing strategy, that includes a set of measures to change either the brand (both for the…

O(1)变换映射,最后一次性替换. #include<bits/stdc++.h> using namespace std; typedef long long ll; ; char s[LEN]; ]; ]; //#define LOCAL int main() { #ifdef LOCAL freopen("in.txt","r",stdin); #endif ; i < ; i++) pos[i] = i; int n, m; scanf(&…

A. Wizards' Duel Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/591/problem/A Description Harry Potter and He-Who-Must-Not-Be-Named engaged in a fight to the death once again. This time they are located at opposite ends of…

A. Combination Lock time limit per test:2 seconds memory limit per test:256 megabytes input:standard input output:standard output Scrooge McDuck keeps his most treasured savings in a home safe with a combination lock. Each time he wants to put there…

A. Joysticks time limit per test:1 second memory limit per test:256 megabytes input:standard input output:standard output Friends are going to play console. They have two joysticks and only one charger for them. Initially first joystick is charged at…

https://codeforces.com/contest/1121/problem/D 题意 给你一个m(<=5e5)个数的序列,选择删除某些数,使得剩下的数按每组k个数以此分成n组(n*k<=m),存在只要一组满足和目标集合s(|s|<=k)匹配(即集合中存在的数,组内一定存在) 题解 重点:找出至少一组满足要求的数 假设[l,r]内满足要求,还需要满足:\((l-1)/k*k+(m-r)/k*k>=k*(n-1)\),可以用双指针,对于每个l可以处理出最小的r满足要求 这样…

A. Snacktower 题目连接: http://codeforces.com/contest/767/problem/A Description According to an old legeng, a long time ago Ankh-Morpork residents did something wrong to miss Fortune, and she cursed them. She said that at some time n snacks of distinct s…

http://codeforces.com/problemset/problem/590/A: 在CF时没做出来,当时直接模拟,然后就超时喽. 题意是给你一个0 1串然后首位和末位固定不变,从第二项开始到倒数第二项,当前的a[i]=(a[i-1],a[i],a[i+1])三项排序后的中间项,比如连续3项为 1 0 1,那么中间的就变为1,然后题目让你输出达到稳定状态时所需的最小步数,不能的话输出-1. 无论给你啥数列,都能达到稳态.所以不可能输出-1: 还有一开始就稳定不变,或经过几次变换而稳定…