网络流--最小费用最大流MUMF模板

 1 #include<stdio.h>        //大概这么多头文件昂
 2 #include<string.h>
 3 #include<vector>
 4 #include<queue>
 5 #include<algorithm>
 6 using namespace std;
 7 const int maxm=10000+100;    //最大点数
 8 const int INF=0x3f3f3f3f;
 9 
10 struct edge{        //边：起点、终点、容量、流量、单位费用
11     int from,to,c,f,cost;
12     edge(int a,int b,int m,int n,int p):from(a),to(b),c(m),f(n),cost(p){}
13 };
14 
15 int aabs(int a){
16     return a>=0?a:-a;
17 }
18 
19 struct MUMF{
20     int m,s,t;
21     vector<edge>e;
22     vector<int>g[maxm];
23     int dis[maxm],a[maxm],p[maxm];
24     bool vis[maxm];
25 
26     void init(int n){        //初始化函数
27         for(int i=0;i<=n;i++)g[i].clear();
28         e.clear();
29     }
30 
31     void add(int a,int b,int c,int v){    //加边函数
32         e.push_back(edge(a,b,c,0,v));
33         e.push_back(edge(b,a,0,0,-v));
34         m=e.size();
35         g[a].push_back(m-2);
36         g[b].push_back(m-1);
37     }
38 
39     bool spfa(int& flow,int& cost){
40         memset(dis,0x3f,sizeof(dis));
41         memset(vis,0,sizeof(vis));
42         queue<int>q;
43         q.push(s);
44         vis[s]=1;
45         dis[s]=0;
46         p[s]=0;
47         a[s]=INF;
48         while(!q.empty()){
49             int u=q.front();q.pop();
50             vis[u]=0;
51             for(int i=0;i<g[u].size();i++){
52                 edge tmp=e[g[u][i]];
53                 if(dis[tmp.to]>dis[u]+tmp.cost&&tmp.c>tmp.f){
54                     dis[tmp.to]=dis[u]+tmp.cost;
55                     p[tmp.to]=g[u][i];
56                     a[tmp.to]=min(a[u],tmp.c-tmp.f);
57                     if(!vis[tmp.to]){
58                         q.push(tmp.to);
59                         vis[tmp.to]=1;
60                     }
61                 }
62             }
63         }
64         if(dis[t]==INF)return 0;
65         flow+=a[t];
66         cost+=dis[t]*a[t];
67         int u=t;
68         while(u!=s){
69             e[p[u]].f+=a[t];
70             e[p[u]^1].f-=a[t];
71             u=e[p[u]].from;
72         }
73         return 1;
74     }
75 
76     int MF(int s,int t){        调用的计算最小费用函数
77         this->s=s;this->t=t;
78         int flow=0,cost=0;
79         while(spfa(flow,cost));
80         return cost;
81     }
82 
83 };