HDU3996 Gold Mine（最大权闭合子图）

 #include<cstdio>
 #include<cstring>
 #include<queue>
 #include<algorithm>
 using namespace std;
 #define INF (1LL<<60)
 #define MAXN 3333
 #define MAXM 3333*3333*2

 struct Edge{
     int v,next;
     __int64 cap,flow;
 }edge[MAXM];
 int vs,vt,NE,NV;
 int head[MAXN];

 void addEdge(int u,int v,__int64 cap){
     edge[NE].v=v; edge[NE].cap=cap; edge[NE].flow=;
     edge[NE].next=head[u]; head[u]=NE++;
     edge[NE].v=u; edge[NE].cap=; edge[NE].flow=;
     edge[NE].next=head[v]; head[v]=NE++;
 }

 int level[MAXN];
 int gap[MAXN];
 void bfs(){
     memset(level,-,sizeof(level));
     memset(gap,,sizeof(gap));
     level[vt]=;
     gap[level[vt]]++;
     queue<int> que;
     que.push(vt);
     while(!que.empty()){
         int u=que.front(); que.pop();
         for(int i=head[u]; i!=-; i=edge[i].next){
             int v=edge[i].v;
             if(level[v]!=-) continue;
             level[v]=level[u]+;
             gap[level[v]]++;
             que.push(v);
         }
     }
 }

 int pre[MAXN];
 int cur[MAXN];
 __int64 ISAP(){
     bfs();
     memset(pre,-,sizeof(pre));
     memcpy(cur,head,sizeof(head));
     int u=pre[vs]=vs;
     __int64 flow=,aug=INF;
     gap[]=NV;
     while(level[vs]<NV){
         bool flag=false;
         for(int &i=cur[u]; i!=-; i=edge[i].next){
             int v=edge[i].v;
             if(edge[i].cap!=edge[i].flow && level[u]==level[v]+){
                 flag=true;
                 pre[v]=u;
                 u=v;
                 //aug=(aug==-1?edge[i].cap:min(aug,edge[i].cap));
                 aug=min(aug,(__int64)edge[i].cap-edge[i].flow);
                 if(v==vt){
                     flow+=aug;
                     for(u=pre[v]; v!=vs; v=u,u=pre[u]){
                         edge[cur[u]].flow+=aug;
                         edge[cur[u]^].flow-=aug;
                     }
                     //aug=-1;
                     aug=INF;
                 }
                 break;
             }
         }
         if(flag) continue;
         int minlevel=NV;
         for(int i=head[u]; i!=-; i=edge[i].next){
             int v=edge[i].v;
             if(edge[i].cap!=edge[i].flow && level[v]<minlevel){
                 minlevel=level[v];
                 cur[u]=i;
             }
         }
         if(--gap[level[u]]==) break;
         level[u]=minlevel+;
         gap[level[u]]++;
         u=pre[u];
     }
     return flow;
 }

 int main(){
     int t,n,m,a,b,c;
     scanf("%d",&t);
     for(int cse=; cse<=t; ++cse){
         scanf("%d",&n);

         vs=; vt=; NV=; NE=;
         memset(head,-,sizeof(head));

         __int64 res=;
         for(int i=; i<=n; ++i){
             scanf("%d",&m);
             for(int j=; j<=m; ++j){
                 scanf("%d%d%d",&a,&b,&c);

                 if(b>a) addEdge(vs,i*+j,b-a),res+=b-a;
                 else addEdge(i*+j,vt,a-b);

                 while(c--){
                     scanf("%d%d",&a,&b);
                     addEdge(i*+j,a*+b,INF);
                 }
             }
         }
         printf("Case #%d: %I64d\n",cse,res-ISAP());
     }
     return ;
 }