Lara Croft, the fiercely independent daughter of a missing adventurer, must push herself beyond her limits when she discovers the island where her father disappeared. In this mysterious island, Lara finds a tomb with a very heavy door. To open the do…

上次周赛碰到这个题目,居然都没思路,真是不应该啊,起码也应该想到枚举法. 因为题目只允许每一row进行reverse操作,而每两列可以进行交换操作,所以首先把row的变化固定下来,即枚举第一列与第1-m列进行交换,之后逐个检查每一行第一列的状态 与 终态是否一致,不一致的话则该行就一定要进行reverse操作了,这样下来,每次枚举就把row的reverse变化给固定下来,接下来只要枚举 接下来的2-m行互相的列变换即可,只需一个嵌套循环即可,总的循环也只是三重 而n和m仅有100,规模承担的起…

D. Diverse Garland time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You have a garland consisting of nn lamps. Each lamp is colored red, green or blue. The color of the ii-th lamp is sisi ('…

D. Jerry's Protest time limit per test:2 seconds memory limit per test:256 megabytes input:standard input output:standard output Andrew and Jerry are playing a game with Harry as the scorekeeper. The game consists of three rounds. In each round, Andr…

题目链接: B. Restoring Painting time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Vasya works as a watchman in the gallery. Unfortunately, one of the most expensive paintings was stolen while he…

You have a garland consisting of nn lamps. Each lamp is colored red, green or blue. The color of the ii-th lamp is sisi ('R', 'G' and 'B' - colors of lamps in the garland). You have to recolor some lamps in this garland (recoloring a lamp means chang…

Andrew often reads articles in his favorite magazine 2Char. The main feature of these articles is that each of them uses at most two distinct letters. Andrew decided to send an article to the magazine, but as he hasn't written any article, he just de…

Hidden Code 题目连接: http://codeforces.com/gym/100015/attachments Description It's time to put your hacking skills to the test! You've been called upon to help crack enemy codes in the current war on... something or another. Anyway, the point is that yo…

https://codeforces.com/contest/1132/problem/C 枚举 + 差分前缀和 题意 有一段[1,n]的线段,有q个区间,选择其中q-2个区间,使得覆盖线段上的点最多为多少? 题解 一开始用贪心搞,搞到一半发现需要枚举的情况太多 只能用暴力搞,即枚举被去掉的两个区间,那么如何判断去掉哪两个区间比较好? 维护去掉后剩下的点数即答案 代码 #include<bits/stdc++.h> using namespace std; int n,q,i,j,l[5005…

题目链接: http://codeforces.com/contest/651/problem/D D. Image Preview time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Vasya's telephone contains n photos. Photo number 1 is currently opened on…

Winter is here at the North and the White Walkers are close. John Snow has an army consisting of n soldiers. While the rest of the world is fighting for the Iron Throne, he is going to get ready for the attack of the White Walkers. He has created a m…

A. ArielTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100685/problem/A Description King Triton really likes watching sport competitions on TV. But much more Triton likes watching live competitions. So Triton decides to set up…

G. #TheDress Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100637/problem/G Description After landing on planet i1c5l people noticed that blue and black clothes are quite popular among the locals. Each aboriginal has at least…

Couple Cover Time Limit: 3000MS   Memory Limit: 524288KB   64bit IO Format: %I64d & %I64u Description 方宝宝有n个篮球,每个篮球上写有一个值ai.他第一次从n个篮球中取出1个,不放回.第二次再在剩余的篮球中取出一个. (每个球被取概率相同).如果这两个球上的值的乘积大于等于p,他会变得高兴,然后请大家吃饭.否则方宝宝会不高兴, 然后暴食暴饮变得更胖. 当然为了方宝宝的健康(被请吃饭),我想取一个…

一个暴力的枚举,枚举组成正多边形需要对应覆盖原先的几条边,范围为(1,n/3),然后维护最大值就可以了,注意初始化为-inf. #include<stdio.h> #include<iostream> #include<string.h> #include<algorithm> using namespace std; ]; int main() { int n; while(~scanf("%d",&n)){ ; ;i<n…

codeforces 895A Pizza Separation 题目大意: 分成两大部分,使得这两部分的差值最小(注意是圆形,首尾相连) 思路: 分割出来的部分是连续的,开二倍枚举. 注意不要看成01背包,一定多读题 代码: #include <bits/stdc++.h> using namespace std; int a[800]; int main() { int n,minval,sum,tot; cin>>n; tot=0; for(int i=1;i<=n;+…

Fliptile Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 14297   Accepted: 5257 Description Farmer John knows that an intellectually satisfied cow is a happy cow who will give more milk. He has arranged a brainy activity for cows in whic…

题目链接:http://codeforces.com/problemset/problem/1108/D time limit per test 1 secondmemory limit per test 256 megabytesinput standard inputoutput standard output You have a garland consisting of n lamps. Each lamp is colored red, green or blue. The colo…

题意 给出一个二进制数\(n\),每次操作可以将一个整数\(x\)简化为\(x\)的二进制表示中\(1\)的个数,如果一个数简化为\(1\)所需的最小次数为\(k\),将这个数叫做特殊的数, 问从\(1\)到\(n\)一共有多少个特殊的数,答案对\(1e9+7\)取模. 分析 \(n\)最大为\(2^{1000}\),二进制表示中最多有\(1000\)个\(1\),所以\(n\)以内的数经过一次简化后将变为\(1000\)以内的数,我们可以暴力打表\(1000\)以内的数简化为\(1\)所需的最…

题目链接:Codeforces 460E Roland and Rose 题目大意:在以原点为圆心,半径为R的局域内选择N个整数点,使得N个点中两两距离的平方和最大. 解题思路:R最大为30.那么事实上距离圆心距离最大的整数点只是12个最多,直接暴力枚举. #include <cstdio> #include <cstring> #include <vector> #include <algorithm> using namespace std; struc…

原题链接:http://codeforces.com/gym/100203/attachments/download/1702/statements.pdf 题解 考虑暴力的复杂度是O(n^3),所以我们需要记录所有的ai+aj,如果当前考虑到了ak,那么就去前面寻找ai,使得ak-ai是我们记录过的和.整个算法的复杂度O(n^2). 代码 #include<iostream> #include<cstring> #include<cstdio> #include<…

题目链接: http://codeforces.com/contest/665/problem/C 题意: 改变最少的字符,使得最终序列无相同的连续的字符. 分析: 对每一个与前一个字符相同的字符,枚举满足条件的字符进行替换. 代码: #include<iostream> using namespace std; int main (void) { string s;cin>>s; int n = s.length(); for(int i = 1; i < n; i++){…

Vasya and Beautiful Arrays CodeForces - 354C Vasya's got a birthday coming up and his mom decided to give him an array of positive integers a of length n. Vasya thinks that an array's beauty is the greatest common divisor of all its elements. His mom…

原题链接:http://codeforces.com/problemset/problem/850/A 题意:有n个五维空间内的点,如果其中三个点A,B,C,向量AB,AC的夹角不大于90°,则点A是“bad”的否则是“good”.题目让我们输出good的点. 思路:从2,3维空间超过5,7个点时不存在“good”的点,可以简单推知五维空间内,超过11个点时不存在“good”的点,那么点数小于11时暴力,大于11时输出0. 其实由于数据量小,直接暴力也是可行的. AC代码: #include<i…

B. Tennis Game time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Petya and Gena love playing table tennis. A single match is played according to the following rules: a match consists of mult…

#点击传送 题目描述 Recently Vasya found a golden ticket - a sequence which consists of nn digits a1a2-ana1a2-an. Vasya considers a ticket to be lucky if it can be divided into two or more non-intersecting segments with equal sums. For example, ticket 3501783…

http://codeforces.com/problemset/problem/749/C 题意:有n个人投票,分为 D 和 R 两派,从1~n的顺序投票,轮到某人投票的时候,他可以将对方的一个人KO,被KO的人不能投票了,这样循环,直到某一派的人全部被KO,问哪方赢. 思路:模拟..代码好懂.. #include <cstdio> #include <algorithm> #include <iostream> #include <cstring> #i…

题意: 有两个点喷水,有很多个点有花,给出坐标. 求使得每个花都可以被喷到,两个喷水的半径的平方的和最小是多少. 思路: 枚举其中一个喷水的最大半径. 坑: 这题我贪心的思路有很大问题.一开始也是想这样枚举的,但是思路超级混乱,按照r2进行贪心但是最后想想想法很荒谬. 顺序和题意一定要搞的很透彻才可以== #include<stdio.h> #include<string.h> #include<algorithm> using namespace std; struc…

题意:给定 n 个数,问你从有多少下标 i < j,并且 ai + aj 是2的倍数. 析:方法一: 从输入开始暴力,因为 i < j 和 i > j 是一样,所以可以从前面就开始查找,然后计数,用个map就搞定,不过时间有点长,接近两秒. 方法二: 先排序,然后暴力,暴力的原则是找前面的,也是用map查找,时间62ms. 代码如下: #include <cstdio> #include <string> #include <cstdlib> #inc…

题目链接: B. Skills time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Lesha plays the recently published new version of the legendary game hacknet. In this version character skill mechanism was…