You're giving a party in the garden of your villa by the sea. The party is a huge success, and everyone is here. It's a warm, sunny evening, and a soothing wind sends fresh, salty air from the sea. The evening is progressing just as you had imagined.…
链接:https://www.nowcoder.com/acm/contest/143/E来源:牛客网 Nowcoder University has 4n students and n dormitories ( Four students per dormitory). Students numbered from 1 to 4n. And in the first year, the i-th dormitory 's students are (x1[i],x2[i],x3[i],x4[…
Strategic Game Time Limit: 20000/10000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 7651 Accepted Submission(s): 3645 Problem Description Bob enjoys playing computer games, especially strategic games, but somet…
http://acm.hdu.edu.cn/showproblem.php?pid=3729 I'm Telling the Truth Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1427 Accepted Submission(s): 719 Problem Description After this year’s col…
题目大意 一个a * b * c(a * b * c <= 5000)大小的长方体中有一些点需要被覆盖,每次可以选择任意大小的长方体,覆盖其中的点,产生的代价为这个长方体长宽高中最小的那个的长度,求最小代价. 二维情形 对二维的情形这就是经典的最小割问题了,可以建立二分图用二分图最大匹配算法解决.具体建图方法是将行和列分为两个集合,如果一个点需要被覆盖,就将它所在的行和列连接起来.这种解法的正确性是显然的:由最大流-最小割定理,最大流就等于最小割,而将行和列连起来后,为保证源与汇分开必须将源到行…