题目链接: Hdu 5352 MZL's City 题目描述: 有n各节点,m个操作.刚开始的时候节点都是相互独立的,一共有三种操作: 1:把所有和x在一个连通块内的未重建过的点全部重建. 2:建立一条双向路(x,y) 3:又发生了地震,p条路被毁. 问最后最多有多少个节点被重建,输出重建节点的最小字典序. 解题思路: 这几天正好在学匹配,但是昨天下午还是没有看出来这个是匹配题目.看了题解扪心自问了自己三次,是不是傻.就是把每个需要重建的节点x拆成k个点,然后对每个拆分后的点和与拆点在同一连通块…

MZL's City Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 710    Accepted Submission(s): 245 Problem Description MZL is an active girl who has her own country. Her big country has N cities numb…

题目大意: 一个地方的点和道路在M年前全部被破坏,每年可以有三个操作, 1.把与一个点X一个联通块内的一些点重建,2.连一条边,3.地震震坏一些边,每年最多能重建K个城市,问最多能建多少城市,并输出操作要让字典序最小 思路: trivial:显然每年向当年可以建的城市连边,每年可以匹配最多K个城市,嗯,很明显的网络流思路,可这样方案数不太好输出 full:再仔细想想这就是多对一的多重匹配,跑一跑匈牙利就可以,K个城市可以拆点,当然简单的方法直接跑K次也可以(想一想为什么) 为了字典序最小,我们要…

MZL's City Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 743    Accepted Submission(s): 260 Problem Description MZL is an active girl who has her own country. Her big country has N cities numb…

最小费用最大流,因为要控制字典序,网络流控制不好了...一直WA,所以用了费用流,时间早的费用大,时间晚的费用少. 构图: 建立一个超级源点和超级汇点.超级源点连向1操作,容量为K,费用为COST,然后COST-1,因为下一次遇到1操作,费用为减少1,即COST-1: 每个1操作连向当前能建造的城市,容量为1,费用为0: 每个城市连向汇点,容量为1,费用为0: #include<cstdio> #include<cstring> #include<cmath> #inc…

题目链接:http://poj.org/problem?id=2289 Jamie's Contact Groups Time Limit: 7000MS   Memory Limit: 65536K Total Submissions: 8473   Accepted: 2875 Description Jamie is a very popular girl and has quite a lot of friends, so she always keeps a very long con…

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…

题意:有N(1<=N<=1e5)个人要移民到M(1<=M<=10)个星球上,每个人有自己想去的星球,每个星球有最大承载人数.问这N个人能否移民成功. 分析:可以用最大流的思路求解该问题,新建源点和汇点,源点与人间加入弧,流量为他想去的星球之和:星球和汇点间加入弧,流量为其承载数量:人和星球间加入弧,流量无限.但是本题中N很大,M却很小,所以想去星球的编号组成的二进制数最多不超过1024,那么可以将N个人缩点.然后跑最大流,满流为N. #include<iostream>…

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…

Escape Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 10382    Accepted Submission(s): 2485 Problem Description 2012 If this is the end of the world how to do? I do not know how. But now scient…