s <= c是最骚的,数组在那一维开了10,第八组样例直接爆了- - /* CodeForces 835C - Star sky [ 前缀和,容斥 ] | Codeforces Round #427 (Div. 2) 题意: 有一片 100*100 的星空,上面有 n 颗星星,每个星星有一个亮度,且在 0~C 范围内周期性变化,现在给出 q 个查询,每个查询给出时间和一个矩形,求在该时间时矩形内星星的亮度和. c <= 10 分析: 由于 c <= 10,则星星的亮度只有11种情况,全部…

证明在Tutorial的评论版里 /* CodeForces 835D - Palindromic characteristics [ 分析,DP ] | Codeforces Round #427 (Div. 2) 题意: 定义 k 回文串满足: 1. 左右子串相等 2. 左右子串为k-1回文串 1 回文串 就是回文串 问你字符串s的子串的每阶回文子串的数目 分析: 研究一下可以发现 k 回文串的要求等价于 1. 本身是回文串 2. 左右子串是k-1回文串 然后可以dp了,还有一个结论是: 若…

Beru-taxi 题目链接: http://codeforces.com/contest/706/problem/A Description Vasiliy lives at point (a, b) of the coordinate plane. He is hurrying up to work so he wants to get out of his house as soon as possible. New app suggested n available Beru-taxi…

Codeforces Round #575 (Div. 3) 这个div3打的太差了,心态都崩了. B. Odd Sum Segments B 题我就想了很久,这个题目我是找的奇数的个数,因为奇数想分成x个奇数,那么这个x肯定是一个奇数, 偶数同理,如果一个偶数想分成y个奇数,那么这个y肯定是一个偶数. 所以数奇数的个数,如果奇数有x个,x是偶数,那么k一定是一个偶数,如果x是一个奇数,那么k肯定是一个奇数. 输出也比较简单,因为奇数要分成奇数个,所以可以前面每组都是含有一个奇数,最后肯定会有奇…

A. Uncowed Forces Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/604/problem/A Description Kevin Sun has just finished competing in Codeforces Round #334! The round was 120 minutes long and featured five problems with maxi…

Palindromic characteristics of string s with length |s| is a sequence of |s| integers, where k-th number is the total number of non-empty substrings of s which are k-palindromes. A string is 1-palindrome if and only if it reads the same backward as f…

The Cartesian coordinate system is set in the sky. There you can see n stars, the i-th has coordinates (xi, yi), a maximum brightness c, equal for all stars, and an initial brightness si (0 ≤ si ≤ c). Over time the stars twinkle. At moment 0 the i-th…

Two boys decided to compete in text typing on the site "Key races". During the competition, they have to type a text consisting of s characters. The first participant types one character in v1 milliseconds and has ping t1 milliseconds. The secon…

引子: A题过于简单导致不敢提交,拖拖拉拉10多分钟还是决定交,太冲动交错了CE一发,我就知道又要错过一次涨分的机会.... B题还是过了,根据题意目测数组大小开1e5,居然蒙对,感觉用vector更好一点... C题WA第9组,GG思密达....明天起床再补C吧 - - 题目链接: http://codeforces.com/contest/835/problem/B B. The number on the board Some natural number was written on t…

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…