Problem H. Hard TestTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100342/attachments Description Andrew is having a hard time preparing his 239-th contest for Petrozavodsk. This time the solution to the problem is based on Di…

Problem H. Horrible Truth Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100610 Description In a Famous TV Show “Find Out” there are n characters and only one Horrible Truth. To make the series breathtaking all way long, the sc…

Problem E. Explicit Formula Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100610 Description Consider 10 Boolean variables x1, x2, x3, x4, x5, x6, x7, x8, x9, and x10. Consider all pairs and triplets of distinct variables amon…

Problem H. Hiking in the Hills 题目连接: http://codeforces.com/gym/100531/attachments Description Helen is hiking with her friends in a highland. Their plan is to hike from their camp A to a beautiful showplace B. Unfortunately, Helen started feeling diz…

D. Optimal Number Permutation 题目连接: http://www.codeforces.com/contest/622/problem/D Description You have array a that contains all integers from 1 to n twice. You can arbitrary permute any numbers in a. Let number i be in positions xi, yi (xi < yi) i…

L. Ministry of Truth Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100187/problem/K Description Andrey works in the Ministry of Truth. His work is changing articles in newspapers and magazines so that they praise the Party an…

题目链接:https://codeforces.com/gym/102361/problem/A 题意:给定二维平面上的\(n\)个点,\(q\)次询问,每次加入一个点,询问平面上有几个包含该点的直角三角形. 分析:这是一篇鸽了很久的题解,主要原因就是现场赛的时候这题惨遭卡常,锅++.现在回过头来想这题,主要问题出在现场赛时误判了\(map\)的时间复杂度,把极角排序的正确想法成功叉掉,以及现场赛时候的共线计数使用了\(gcd\),使得整体复杂度上升.(但还是有大佬拿gcd思想过了,我太菜了)现…

题意 Split a unique array into two almost unique arrays. unique arrays指数组各个数均不相同,almost unique arrays指可以删掉数后再判断. 思路 略神的数学构造题... 官方题解: An equivalent definition for almost unique, is arrays with at least ⌊ 2n / 3⌋ different elements. The idea is to split…

Problem A. Alien Communication Masterclass Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100610 Description Andrea is a famous science fiction writer, who runs masterclasses for her beloved readers. The most popular one is the…

Problem J. Triatrip Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100342/attachments Description The travel agency “Four Russians” is offering the new service for their clients. Unlike other agencies that only suggest one-way…

Problem C. Painting CottagesTime Limit: 2 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100342/attachments Description The new cottage settlement is organized near the capital of Flatland. The construction company that is building the settl…

Problem C. Painting CottagesTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100342/attachments Description The new cottage settlement is organized near the capital of Flatland. The construction company that is building the sett…

Problem F. Door LockTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100500/attachments Description It was a beautiful night at Yekaterinburg, the sky was crystal clear with no clouds, and the view of the moon and the stars was…

Problem K. Kitchen Robot Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100610 Description Robots are becoming more and more popular. They are used nowadays not only in manufacturing plants, but also at home. One programmer wit…

Problem F "Folding" Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100002 Description Bill is trying to compactly represent sequences of capital alphabetic characters from 'A' to 'Z' by folding repeating subsequences insid…

Problem J. TriatripTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100342/attachments Description The travel agency “Four Russians” is offering the new service for their clients. Unlike other agencies that only suggest one-way…

Problem E. MinimaTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100342/attachments Description You are given an array x[1 . . . n] and a number m. For all i from 1 to n−m+ 1 find the minimum among x[i], x[i + 1], . . . , x[i +…

Problem D. Dinner ProblemTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100342/attachments Description A group of k students from Cooking University living in the campus decided that each day of the semester one of them will p…

题目链接: http://codeforces.com/gym/100342 题意: 求三元环的个数 题解: 用bitset分别统计每个点的出度的边和入度的边. 枚举每一条边(a,b),计算以b为出度的边的终点构成的点集和以a为入度的边的起点够成的点集的交集,更新答案. 代码: #include<iostream> #include<cstring> #include<cstdio> #include<bitset> using namespace std;…

Problem F. Fibonacci SystemTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hust.edu.cn/vjudge/contest/view.action?cid=86821#problem/B Description Little John studies numeral systems. After learning all about fixed-base systems, he became inte…

C. Necklace 题目连接: http://www.codeforces.com/contest/613/problem/C Description Ivan wants to make a necklace as a present to his beloved girl. A necklace is a cyclic sequence of beads of different colors. Ivan says that necklace is beautiful relative…

C - Will It Stop?Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hust.edu.cn/vjudge/contest/view.action?cid=87794#problem/C Description Byteasar was wandering around the library of the University of Warsaw and at one of its facades he noticed…

Problem D. Distance 题目连接: http://codeforces.com/gym/100714 Description In a large city a cellular network operator is holding a competition for subscribers to promote their new "pedestrian navigator" service. The main prize will be awarded to th…

题意: 给出n个点m条公路k条铁路. 接下来m行 u v w      //u->v 距离w 然后k行 v w         //1->v 距离w 如果修建了铁路并不影响两点的最短距离,那么修铁路是没必要的 求能删掉多少条铁路 题解: 把公路和铁路放一起构成一个图,然后跑一边最短路.最后如果最短路结果小于铁路的长度,那么这条铁路就没必要修 如果最短路结果等于铁路的长度,要先判断一下这个最短路是不是一条,如果这条最短路个数多于一条那么这条铁路就没必要修 怎么判断最短路路径数是不是大于1? 1…

H. Mysterious Photos Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100187/problem/H Description Everyone probably heard the rumours about the constellation of Bermuda Triangle: any person who looks to this constellation of th…

一句话题意:x0=1,xi+1=(Axi+xi%B)%C,如果x序列中存在最早的两个相同的元素,输出第二次出现的位置,若在2e7内无解则输出-1. 题解:都不到100天就AFO了才来学这floyd判圈算法. 介绍一下floyd判圈算法:该算法适用于在线性时间复杂度内判断有限自动机.迭代函数.链表中是否有环,求环的起点(即链长)和环长. 可以先这么做:首先从起点S出发,给定两个指针,一个快指针一个慢指针,然后每次快指针走1步,慢指针走2步,直到相遇为止.如果已经到达终点/达到规定步数时仍然没有相遇…

H - Football BetsTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hust.edu.cn/vjudge/contest/view.action?cid=87493#problem/H Description While traveling to England, it is impossible not to catch the English passion for football. Almost everyon…

K. Perpetuum Mobile Time Limit: 2 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100187/problem/K Description The world famous scientist Innokentiy almost finished the creation of perpetuum mobile. Its main part is the energy generator which…

Problem H. ICPC QuestTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100500/attachments Description Coach Fegla has invented a song effectiveness measurement methodology. This methodology in simple English means count the frequ…

Problem H. Hell on the MarketsTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hust.edu.cn/vjudge/contest/view.action?cid=86821#problem/H Description Most financial institutions had become insolvent during financial crisis and went bankrupt or…