题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1669 思路:由于要求minimize the size of the largest group,由此我们想到二分枚举,然后每一次求一下多重匹配就可以了. #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #include<vector> using n…

Jamie's Contact Groups Time Limit: 15000/7000 MS (Java/Others)    Memory Limit: 65535/65535 K (Java/Others)Total Submission(s): 747    Accepted Submission(s): 303 Problem Description Jamie is a very popular girl and has quite a lot of friends, so she…

Jamie's Contact Groups Time Limit: 15000/7000 MS (Java/Others)    Memory Limit: 65535/65535 K (Java/Others)Total Submission(s): 552    Accepted Submission(s): 190 Problem Description Jamie is a very popular girl and has quite a lot of friends, so she…

题目链接:http://poj.org/problem?id=2112 思路:由于要求奶牛走的最远距离的最短路程,显然我们可以二分距离,如果奶牛与挤奶器的距离小于等于limit的情况下,能够满足,则在(low,limit-1)中继续二分,否则在(limit+1,high)中寻找,那满足的条件就是根据题目的条件每头奶牛都能找到挤奶器,由于每个挤奶器可以最多挤M头奶牛,因此要求多重匹配. 注意点:一开始要Floyd预处理出每头奶牛到挤奶器的最短距离. http://paste.ubuntu.com/…

Escape Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 8747    Accepted Submission(s): 2026 Problem Description 2012 If this is the end of the world how to do? I do not know how. But now scienti…

Jamie's Contact Groups Time Limit: 7000MS   Memory Limit: 65536K Total Submissions: 9227   Accepted: 3180 Description Jamie is a very popular girl and has quite a lot of friends, so she always keeps a very long contact list in her cell phone. The con…

Escape Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 13005    Accepted Submission(s): 3258 Problem Description 2012 If this is the end of the world how to do? I do not know how. But now scient…

Battle ships Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 39    Accepted Submission(s): 19 Problem Description Dear contestant, now you are an excellent navy commander, who is responsible of…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1669 题目大意: 给你各个人可以属于的组,把这些人分组,使这些组中人数最多的组人数最少,并输出这个人数.解题思路: 一组可以有多人,一人只能分到一组,显然是多重匹配,只要枚举一下每组的限制人数limit,用多重匹配判断即可. 代码 #include<iostream> #include<cstdio> #include<cstring> #include<algori…

二分匹配:二分图的一些性质 二分图又称作二部图,是图论中的一种特殊模型. 设G=(V,E)是一个无向图,如果顶点V可分割为两个互不相交的子集(A,B),并且图中的每条边(i,j)所关联的两个顶点i和j分别属于这两个不同的顶点集(i in A,j in B),则称图G为一个二分图. 1.一个二分图中的最大匹配数等于这个图中的最小点覆盖数 König定理是一个二分图中很重要的定理,它的意思是,一个二分图中的最大匹配数等于这个图中的最小点覆盖数.如果你还不知道什么是最小点覆盖,我也在这里说一下:假如选…