Cyclic Tour Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/65535 K (Java/Others)Total Submission(s): 1197    Accepted Submission(s): 626 Problem Description There are N cities in our country, and M one-way roads connecting them. Now Li…

Fire Net Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 7998    Accepted Submission(s): 4573 Problem Description Suppose that we have a square city with straight streets. A map of a city is a s…

小希和Gardon在玩一个游戏:对一个N*M的棋盘,在格子里放尽量多的一些国际象棋里面的“车”,并且使得他们不能互相攻击,这当然很简单,但是Gardon限制了只有某些格子才可以放,小希还是很轻松的解决了这个问题(见下图)注意不能放车的地方不影响车的互相攻击. 所以现在Gardon想让小希来解决一个更难的问题,在保证尽量多的“车”的前提下,棋盘里有些格子是可以避开的,也就是说,不在这些格子上放车,也可以保证尽量多的“车”被放下.但是某些格子若不放子,就无法保证放尽量多的“车”,这样的格子被称做重要…

链接: http://acm.hdu.edu.cn/showproblem.php?pid=1281 http://acm.hust.edu.cn/vjudge/contest/view.action?cid=82834#problem/D 棋盘游戏 Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 3342    Accepted Sub…

分析:先求出来最大匹配数,然后用匹配的点一个一个去除看看能否达到最大匹配,能的话就是关键点(很暴力啊),不过竟然才31ms ***************************************************************** #include<stdio.h> #include<; ; j<=N; j++)     {         ;     ; i<=M; i++)     {         memset(used, ;     }, p…

Consider a town where all the streets are one-way and each street leads from one intersection to another. It is also known that starting from an intersection and walking through town's streets you can never reach the same intersection i.e. the town's…

The Accomodation of Students Time Limit: 5000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 8418    Accepted Submission(s): 3709 Problem Description There are a group of students. Some of them may know each ot…

题意:交换任意两行或两列,使主对角线全为1. 分析: 1.主对角线都为1,可知最终,第一行与第一列匹配,第二行与第二列匹配,……. 2.根据初始给定的矩阵,若Aij = 1,则说明第i行与第j列匹配,据此求最大匹配数cnt,若cnt==N,才可通过交换使主对角线都为1. 3.交换时,可只交换行或只交换列.如:只交换列,行不变(顺序为1,2,3,……,n),那么对于列,只需要根据选择排序,将每行一开始匹配的列的顺序最终也变成1,2,3,……,n即可,因为是选择排序,每次选择第i小的交换到第i个位置…

Machine Schedule Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 5316    Accepted Submission(s): 2631 Problem Description As we all know, machine scheduling is a very classical problem in comput…

Strategic Game Time Limit: 20000/10000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 4697    Accepted Submission(s): 2125 Problem Description Bob enjoys playing computer games, especially strategic games, but somet…