传送门 分析 看到这个题我们的第一反应自然是Tarjan缩点,在这之后我们可以发现实际只要在缩点之后所有出度或入度为0的点布置警察局就可以达到要求,我们用dpij表示考虑前i个出度或入度为0的点共布置了j个警察局,s[i]表示这个点原先由几个点构成,tot表示出度或入度为0的点的总数,所以不难得到转移方程 所以不难得到最终答案 注意此题需要使用高精度. 代码 #include<iostream> #include<cstdio> #include<cstring> #i…

Police Cities Time Limit: 10 Seconds      Memory Limit: 32768 KB Once upon the time there lived a king and he had a big kingdom. And there were n cities in his kingdom and some of them were connected by the roads. And the roads were all one-way becau…

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…

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…

Inzane finally found Zane with a lot of money to spare, so they together decided to establish a country of their own. Ruling a country is not an easy job. Thieves and terrorists are always ready to ruin the country's peace. To fight back, Zane and In…

Connect the Cities Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 18322 Accepted Submission(s): 4482 Problem DescriptionIn 2100, since the sea level rise, most of the cities disappear. Though some…

Description Meanwhile, the kingdom of K is getting ready for the marriage of the King's daughter. However, in order not to lose face in front of the relatives, the King should first finish reforms in his kingdom. As the King can not wait for his daug…

CF449B CF450D http://codeforces.com/contest/450/problem/D http://codeforces.com/contest/449/problem/B Codeforces Round #257 (Div. 2) D Codeforces Round #257 (Div. 1) B D. Jzzhu and Cities time limit per test 2 seconds memory limit per test 256 megaby…

音乐赏析似乎是一件没有意义的工作,与电影相比音乐更加抽象,不同的人对同一首歌会有完全不同的解读. 但一首歌一旦成为经典,就有解读它的必要,因为它一定诉出了一个群体的某些情绪. Karma police, arrest this man He talks in math He buzzes like a fridge He's like a detuned radio Karma police, arrest this girl Her Hitler hairdo Is making me fee…

Connections between cities Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 4425    Accepted Submission(s): 1263 Problem Description After World War X, a lot of cities have been seriously damag…