D. New Year Letter time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Many countries have such a New Year or Christmas tradition as writing a letter to Santa including a wish list for presents…

题目链接: http://www.codeforces.com/contest/666/problem/B 题意: 给你n个城市,m条单向边,求通过最短路径访问四个不同的点能获得的最大距离,答案输出一个满足条件的四个点. 题解: 首先预处理出任意两点的最短距离,用队列优化的spfa跑:O(n*n*logn) 现依次访问四个点:v1,v2,v3,v4 我们可以枚举v2,v3,然后求出v2的最远点v1,v3的最远点v4,为了保证这四个点的不同,直接用最远点会错,v1,v4相同时还要考虑次最远点来替换…

B. Covered Path Time Limit: 1 Sec  Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/534/problem/B Description The on-board computer on Polycarp's car measured that the car speed at the beginning of some section of the path equals v1 meters per…

题目链接:A. Sereja and Swaps 题意:给定一个序列,能够交换k次,问交换完后的子序列最大值的最大值是多少 思路:暴力枚举每一个区间,然后每一个区间[l,r]之内的值先存在优先队列内,然后找区间外假设有更大的值就替换掉. 求出每一个区间的最大值,最后记录下全部区间的最大值 代码: By lab104_yifan, contest: Codeforces Round #243 (Div. 2), problem: (C) Sereja and Swaps, Accepted, #…

题意:求定 n 个数,求有多少对数满足,ai^bi = x. 析:暴力枚举就行,n的复杂度. 代码如下: #pragma comment(linker, "/STACK:1024000000,1024000000") #include <cstdio> #include <string> #include <cstdlib> #include <cmath> #include <iostream> #include <c…

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 ('…

很简单的暴力枚举,却卡了我那么长时间,可见我的基本功不够扎实. 两个数相乘等于一个数6*n,那么我枚举其中一个乘数就行了,而且枚举到sqrt(6*n)就行了,这个是暴力法解题中很常用的性质. 这道题找出a和b中最小的那个,然后开始枚举,一直枚举到sqrt(6*n)的向上取整.这样所有可能是答案的情况都有啦.再干别的都是重复的或者肯定不是最小面积的. #include<iostream> #include<cstdio> #include<cstdlib> #includ…

就暴力枚举所有起点和终点就行了. 我做这题时想的太多了,最简单的暴力枚举起始点却没想到...应该先想最简单的方法,层层深入. #include<iostream> #include<cstdio> #include<cstdlib> #include<cstring> #include<cmath> #include<map> #include<set> #include<vector> #include<…

B. Laurenty and Shoptime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard outputA little boy Laurenty has been playing his favourite game Nota for quite a while and is now very hungry. The boy wants to make sa…

题目链接: http://codeforces.com/gym/101194/attachments https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=5930 题意: 现有四支队伍两两打比赛,总共就是打六场比赛,每场比赛赢的队伍可得 $3$ 分,输的队伍得 $0$ 分,平局则两个队各得 $1$ 分. 现在给出四个队伍最终的积分…