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…

                                                         Drainage Ditches Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 69983   Accepted: 27151 Description Every time it rains on Farmer John's fields, a pond forms over Bessie's favorit…

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…

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 John has built a set of drainage…

一.题面 Drainage Ditches 二.分析 网络流的裸题. 1 Edmonds-Karp算法 求解网络流其实就是一个不断找增广路,然后每次找到一条增广路后更新残余网络的一个过程. EK算法主要就是用bfs去找增广路,然后不断更新残余网络得到最终答案. 2 Dinic算法 对于Ford-Fulkerson和Edmonds-Karp算法,求解网络流都是一次次用DFS或者BFS,这其实是很费时的,Dinic相当于就是一次BFS然后DFS求解出多条增广路. 3 ISAP 三.AC代码 1 //…

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…

POJ 1273给出M条边,N个点,求源点1到汇点N的最大流量. 本文主要就是附上dinic的模板,供以后参考. #include <iostream> #include <stdio.h> #include <algorithm> #include <queue> #include <string.h> /* POJ 1273 dinic算法模板 边是有向的,而且存在重边,且这里重边不是取MAX,而是累加和 */ using namespace…

题目链接 网络流入门@_@,此处本人用的刘汝佳的Dinic模板 #include<bits/stdc++.h> using namespace std; const int INF = 0x3f3f3f3f; struct Edge { int from,to,cap,flow; }; int n,s,t,m; struct Dinic { , M = ; //N对应点数 vector<Edge> edges; vector<int> G[N]; bool vis[N]…

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>…

Description 给图,求最大流 最大流模板题,这里用dinic Code #include <cstdio> #include <cstring> #include <algorithm> #define Inf 0x7fffffff #define N 210 using namespace std; int g[N][N],d[N],q[N*10],h,t; int n,m,Ans,tmp; bool Bfs(){ memset(d,-1,sizeof(d)…