A. A and B and Chess time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output A and B are preparing themselves for programming contests. To train their logical thinking and solve problems better, A…

B. Bear and Finding Criminals time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output There are n cities in Bearland, numbered 1 through n. Cities are arranged in one long row. The distance betwee…

A. Far Relative's Birthday Cake 题目连接: http://www.codeforces.com/contest/629/problem/A Description Door's family is going celebrate Famil Doors's birthday party. They love Famil Door so they are planning to make his birthday cake weird! The cake is a…

A. Hongcow Learns the Cyclic Shift 题目连接: http://codeforces.com/contest/745/problem/A Description Hongcow is learning to spell! One day, his teacher gives him a word that he needs to learn to spell. Being a dutiful student, he immediately learns how t…

A. Mahmoud and Longest Uncommon Subsequence 题目连接: http://codeforces.com/contest/766/problem/A Description While Mahmoud and Ehab were practicing for IOI, they found a problem which name was Longest common subsequence. They solved it, and then Ehab ch…

A. The New Year: Meeting Friends 题目连接: http://codeforces.com/contest/723/problem/A Description There are three friend living on the straight line Ox in Lineland. The first friend lives at the point x1, the second friend lives at the point x2, and the…

C. Predict Outcome of the Game 题目连接: http://codeforces.com/contest/451/problem/C Description There are n games in a football tournament. Three teams are participating in it. Currently k games had already been played. You are an avid football fan, but…

B. Little Robber Girl's Zoo 题目连接: http://www.codeforces.com/contest/686/problem/B Description Little Robber Girl likes to scare animals in her zoo for fun. She decided to arrange the animals in a row in the order of non-decreasing height. However, th…

B. Alyona and Mex 题目连接: http://www.codeforces.com/contest/682/problem/B Description Someone gave Alyona an array containing n positive integers a1, a2, ..., an. In one operation, Alyona can choose any element of the array and decrease it, i.e. replac…

[CF简单介绍] 提交链接:http://codeforces.com/contest/560/problem/B 题面: B. Gerald is into Art time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Gerald bought two very rare paintings at the Sotheby's a…

D. String Game time limit per test 2 seconds memory limit per test 512 megabytes input standard input output standard output Little Nastya has a hobby, she likes to remove some letters from word, to obtain another word. But it turns out to be pretty…

You are given an array aa consisting of nn integers. In one move, you can choose two indices 1≤i,j≤n1≤i,j≤n such that i≠ji≠j and set ai:=ajai:=aj . You can perform such moves any number of times (possibly, zero). You can choose different indices in d…

题意: 对于26个字母 每个字母分别有一个权值 给出一个字符串,找出有多少个满足条件的子串, 条件:1.第一个字母和最后一个相同,2.除了第一个和最后一个字母外,其他的权和为0 思路: 预处理出sum[i]:s[0~i]的和 开26个map<LL, LL>numV 分别表示 每个字母前缀和 的个数 例如处理到第i个元素,且numV[s[i]-'a'][sum[i]-v[s[i] - 'a']] (值为2) 表示在处理到的元素之前 以s[i]结尾的前缀和为sum[i]-v[s[i]-'a']的个…

水 A. A and B and Chess /* 水题 */ #include <cstdio> #include <algorithm> #include <iostream> #include <cstring> #include <string> using namespace std; const int maxn = 1e6 + 10; int a[maxn]; int main(void) { //freopen ("A.…

D. A and B and Interesting Substrings time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A and B are preparing themselves for programming contests. After several years of doing sports program…

C. A and B and Team Training time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output A and B are preparing themselves for programming contests. An important part of preparing for a competition is s…

B. A and B and Compilation Errors time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A and B are preparing themselves for programming contests. B loves to debug his code. But before he runs t…

A and B and Lecture Rooms time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A and B are preparing themselves for programming contests. The University where A and B study is a set of rooms co…

传送门 D. A and B and Interesting Substrings time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A and B are preparing themselves for programming contests. After several years of doing sports pro…

题目链接 http://codeforces.com/contest/711/problem/C Description ZS the Coder and Chris the Baboon has arrived at Udayland! They walked in the park where n trees grow. They decided to be naughty and color the trees in the park. The trees are numbered wit…

题目链接:http://codeforces.com/contest/832/problem/B B. Petya and Exam time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output It's hard times now. Today Petya needs to score 100 points on Informatics…

A. Little Artem and Presents 题目连接: http://www.codeforces.com/contest/669/problem/A Description Little Artem got n stones on his birthday and now wants to give some of them to Masha. He knows that Masha cares more about the fact of receiving the prese…

C. Alice, Bob and Chocolate 题目连接: http://codeforces.com/contest/6/problem/C Description Alice and Bob like games. And now they are ready to start a new game. They have placed n chocolate bars in a line. Alice starts to eat chocolate bars one by one f…

A. Key races 题目链接:http://codeforces.com/contest/835/problem/A 题目意思:两个比赛打字,每个人有两个参数v和t,v秒表示他打每个字需要多久时间,等这个这个字传递过去需要t秒,而且在打第一个字之前也会有一个反应时间t.问第一个人可不可以获胜. 题目思路:这个题目当时题目没读懂,明白之后就是一个非常简单的题目了. (s*v1+2*t1)<(s*v2+2*t2)第一个人就可以获胜 (s*v1+2*t1)==(s*v2+2*t2) 就会平局,否…

A. Pupils Redistribution time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output In Berland each high school student is characterized by academic performance — integer value between 1 and 5. In hig…

A题英语漏洞 A题传送门: https://codeforces.com/contest/1501/problem/A 其实题目说的很明白, 只是我傻傻的会错了意, 话不多说, 开整. 前两行是说, 火车从i - 1站到 i 站所需时间, 下面的1说的是它在车站上的时间至少为⌈bi−ai⌉/2(除法用上限, 简言之就是带小数的去掉小数, 再加一) 要计算到达的时间, 显然就是这两者之和了, 我当时哈哈, 就判断时间是否大于等于这个第一条, 真爽, 看了半天没用的 传送门_C题: https://…

传送门 Description Chloe, the same as Vladik, is a competitive programmer. She didn't have any problems to get to the olympiad like Vladik, but she was confused by the task proposed on the olympiad. Let's consider the following algorithm of generating a…

D. Ability To Convert time limit per test 1 second Cmemory limit per test 256 megabytes input standard input output standard output Alexander is learning how to convert numbers from the decimal system to any other, however, he doesn't know English le…

先给出比赛地址啦,感觉这场比赛思维考察非常灵活而美妙. A. Odds and Ends ·述大意:      输入n(n<=100)表示长度为n的序列,接下来输入这个序列.询问是否可以将序列划分成奇数个连续部分,使得每一部分满足:开头结尾是奇数,序列长度也是奇数.如果可以输出Yes否则输出No. ·分析:     我们发现这是一道与奇偶性有关的问题,因此尝试进行一些分类讨论来探求解法.序列需要满足什么特点才能满足题目要求呢?      第一个突破口是:"划分成奇数个序列,每个序列长度为奇…

E. Table Compression time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output Little Petya is now fond of data compression algorithms. He has already studied gz, bz, zipalgorithms and many others.…