题目链接: http://codeforces.com/problemset/problem/208/C C. Police Station time limit per test:2 secondsmemory limit per test:256 megabytes 问题描述 The Berland road network consists of n cities and of m bidirectional roads. The cities are numbered from 1 to…

题目链接:http://codeforces.com/contest/208/problem/C 思路:题目要求的是经过1~N的最短路上的某个点的路径数 /  最短路的条数的最大值.一开始我是用spfa得到从1开始的最短路和从N开始的最短路,然后分别从N开始记忆化搜索,得到从1到达最短路径上的u的路径条数,记作dp1[u], 然后再从1开始搜,得到最短路径上从N到达某个点u的路径条数,记作dp2[u],于是经过某个点u的最短路径数目为dp1[u] * dp2[u],然后只需枚举u求最大值即可.…

Codeforces Round #267 (Div. 2) C. George and Job题目链接请点击~ The new ITone 6 has been released recently and George got really keen to buy it. Unfortunately, he didn't have enough money, so George was going to work as a programmer. Now he faced the follow…

地址:http://codeforces.com/contest/796/problem/D 题目: D. Police Stations time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Inzane finally found Zane with a lot of money to spare, so they togeth…

A. Dubstep 字符串模拟. string.find()用法 string str; size_t pos = str.find("WUB"); // 返回匹配的第一个位置 size_t nxt = str.find("WUB", pos); // 返回大于等于pos的第一个匹配位置 // 如果没有找到,则返回std::string::npos B. Solitaire \(dp(i,j,k)\)表示是否能到达倒三张牌分别为\(i,j,k\)的状态. C. P…

题目链接: http://codeforces.com/problemset/problem/208/A A. Dubstep time limit per test:2 secondsmemory limit per test:256 megabytes 问题描述 Vasya works as a DJ in the best Berland nightclub, and he often uses dubstep music in his performance. Recently, he…

题目的意思就是找出未能及时处理的犯罪数, #include <iostream> using namespace std; int main(){ int n; cin >> n; , crimes = ;; ; i < n; ++ i){ cin >> a; ) recruit+=a; else recruit?recruit-- : crimes++; } cout<<crimes<<endl; }…

传送门 题意 n个点有n-1条边相连,其中有k个特殊点,要求: 删去尽可能多的边使得剩余的点距特殊点的距离不超过d 输出删去的边数和index 分析 比赛的时候想不清楚,看了别人的题解 一道将1个联通块转化为k个树的题目,考虑上界,应该是k-1条边,这k-1条边是原图中连接树与树的边,那么我们操作如下: 1.将特殊点i染色为i,放入队列 2.做一次bfs,对每个点相邻的点染色并判断 3.遍历边,如果边的两点不同色,则输出边的index trick 代码 #include <cstdio> #i…

题目链接: http://codeforces.com/problemset/problem/507/E E. Breaking Good time limit per test2 secondsmemory limit per test256 megabytes 问题描述 Breaking Good is a new video game which a lot of gamers want to have. There is a certain level in the game that…

C. Famil Door and Brackets 题目连接: http://www.codeforces.com/contest/629/problem/C Description As Famil Door's birthday is coming, some of his friends (like Gabi) decided to buy a present for him. His friends are going to buy a string consisted of roun…