Drainage DitchesHal Burch Time Limit 1000 ms Memory Limit 65536 kb description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by water for awhile and takes quite a…

最大流的第一道题,刚开始学这玩意儿,感觉好难啊!哎····· 希望慢慢地能够理解一点吧! #include<stdio.h> #include<string.h> #include<queue> using namespace std; #define inf 1000000 #define min(a,b) a<b?a:b int map[210][210],pre[210],maxf[210]; int n,m; int bfs()//搜索,截止找不到增广路…

                                                                                        Drainage Ditches   Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by water f…

题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=1532 感觉题意不清楚,不知道是不是个人英语水平问题.本来还以为需要维护入度和出度来找源点和汇点呢,看讨论才知道1就是起点,m就是汇点..好想把代码写的工程化一点. #include <stdio.h> #include <string.h> #include <queue> #include <algorithm> using namespace std; c…

题目网址:http://acm.hdu.edu.cn/showproblem.php?pid=1532 思路: 网络流最大流的入门题,直接套模板即可~ 注意坑点是:有重边!!读数据的时候要用“+=”替换“=”. 对网络流不熟悉的,给一篇讲解:http://www.cnblogs.com/ZJUT-jiangnan/p/3632525.html. ✧(≖ ◡ ≖✿)我是看这篇博客才入门的. 代码: #include <cstdio> #include <cstring> #inclu…

Drainage Ditches Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 53640   Accepted: 20448 Description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by…

Drainage Ditches Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 14721    Accepted Submission(s): 6968 Problem Description Every time it rains on Farmer John's fields, a pond forms over Bessie's…

A - Drainage Ditches Time Limit:1000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u   Description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by wa…

Drainage Ditches Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 8861    Accepted Submission(s): 4141 Problem Description Every time it rains on Farmer John's fields, a pond forms over Bessie's…

Drainage Ditches Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 65536/32768K (Java/Other) Total Submission(s) : 5   Accepted Submission(s) : 3 Font: Times New Roman | Verdana | Georgia Font Size: ← → Problem Description Every time it rains on…

Drainage Ditches Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 22789    Accepted Submission(s): 10905 Problem Description Every time it rains on Farmer John's fields, a pond forms over Bessie'…

最大流首次体验感受—— 什么是最大流呢? 从一个出发点(源点),走到一个目标点(汇点),途中可以经过若干条路,每条路有一个权值,表示这条路可以通过的最大流量. 最大流就是从源点到汇点,可以通过的最大流量. 接下来我们看一个图—— 图1 这个图中,s是源点,t是汇点.期间可以经过2, 3, 4, 5, 6几个点.每条边上有两个权值,其中第一个表示当前通过这条边的流量,第二个表示这条边最大可以通过的流量. 最佳情况,即最大可以通过的流量的一种情况是这样的—— 图2 但还有一种情况,同样可以达到最大流…

题意: 给出一个有向图,以及边上的容量上限,求最大流.(有重边,要将容量上限叠加) 思路: 用最简单的EK+BFS解决.每次搜到一条到达终点的路径,就立刻退出,更新ans,然后再回头修改图中的当前flow状况(这就得靠记录路径了).当当前图没有到达终点的路径图,流已经饱和,可以结束程序了. #include <bits/stdc++.h> #define LL long long #define pii pair<int,int> #define INF 0x7f7f7f7f us…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1532 题目大意是:农夫约翰要把多个小池塘的水通过池塘间连接的水渠排出去,从池塘1到池塘M最多可以排多少的水流量,给定水渠和连接的两个小池塘,以及该水渠的流量,求最大流. 其实就是裸的最大流,源点是1号池塘,汇点是M号池塘,从1到M做一个dinic算法求出最大流就行,但是我一直WA,怎么也改不对,后来发现是因为自己喜欢用vector建边建图的原因,对于输入多组样例时,没有初始化上组样例的vector数…

题意:输入m n, m是边数,n是点数. 接下来m行: 起点,终点,容量.求以 1 为源点, n为汇点的最大流. #include<stdio.h> #include<string.h> #include<queue> #include<algorithm> using namespace std; const int INF = 0xfffffff; + ; //邻接矩阵存放图. int flow[MAXN][MAXN]; //mark[]标记是否访问过,…

网络最大流模版题,用了(Ford-Fulkerson算法)  代码不贴了,模版见我博客 http://www.cnblogs.com/zufezzt/p/4585752.html  …

题目大意:就是由于下大雨的时候约翰的农场就会被雨水给淹没,无奈下约翰不得不修建水沟,而且是网络水沟,并且聪明的约翰还控制了水的流速, 本题就是让你求出最大流速,无疑要运用到求最大流了.题中m为水沟数,n为水沟的顶点,接下来Si,Ei,Ci分别是水沟的起点,终点以及其容量.求源点1到终点m的最大流速. EK算法详解参考链接 EK模板 #include<iostream> #include<queue> #include<cstring> #include<algor…

还是不是很懂算法 先存一个模板先吧--- 看的这篇学的-- http://www.renfei.org/blog/isap.html #include<cstdio> #include<cstring> #include<iostream> #include<algorithm> #include<vector> #include<queue> using namespace std; ; << ) - ; struct…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1532 Drainage Ditches Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 18864    Accepted Submission(s): 8980 Problem Description Every time it rain…

HDU - 1532 题意:有m个点,n条管道,问从1到m最大能够同时通过的水量是多少? 题解:最大流模板题. #include <iostream> #include <algorithm> #include <cstdio> #include <cstring> #include <queue> using namespace std; typedef long long ll; const int INF = 0x3ffffff; cons…

Drainage Ditches Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 13064    Accepted Submission(s): 6196 Problem Description Every time it rains on Farmer John's fields, a pond forms over Bessie's…

题目链接:poj1273 Drainage Ditches 呜呜,今天自学网络流,看了EK算法,学的晕晕的,留个简单模板题来作纪念... #include<cstdio> #include<vector> #include<queue> #include<cstring> #include<set> #include<algorithm> #define CLR(a,b) memset((a),(b),sizeof((a))) usi…

题目链接:http://poj.org/problem?id=1273 Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by water for awhile and takes quite a long time to regrow. Thus, Farmer John has…

描述 Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by water for awhile and takes quite a long time to regrow. Thus, Farmer John has built a set of drainage ditches s…

题目链接:http://poj.org/problem?id=1273 Time Limit: 1000MS Memory Limit: 10000K Description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by water for awhile and takes…

题目链接: Drainage Ditches Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 67475   Accepted: 26075 Description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is cover…

Drainage Ditches Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 65146 Accepted: 25112 Description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by wate…

http://poj.org/problem?id=1273 Description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by water for awhile and takes quite a long time to regrow. Thus, Farmer Jo…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1532 思路分析:问题为最大网络流问题,给定一个有向图,需要求解该有向图的最大网络流,使用EdmondsKarp算法求解: 需要注意输入的边中可能有重边的存在: 代码如下: #include <queue> #include <vector> #include <cstdio> #include <climits> #include <cstring>…

解题关键:最大流裸题 #include<cstdio> #include<cstring> #include<algorithm> #include<cstdlib> #include<cmath> #include<iostream> #include<queue> #include<vector> #define inf 0x3f3f3f3f #define MAX_V 252 using namespac…