pku 1149 最大流

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#include<stdio.h>
#include<string.h>
#define min(a,b)(a<b?a:b)
#define INF 9999999
#define MAX 1005
int S,N,end,M;
int cap[MAX][MAX],flow[MAX],p[MAX];
int room[MAX],belong[MAX];
int q[10000];
int bfs()
{
int u,i;
for(i=0;i<MAX;i++)
    {
        flow[i]=INF;
        p[i]=-1;
    }
    p[S]=0;
int front=0,rear=1;
    q[front]=S;
while(front<rear)
    {
        u=q[front++];
if(u==end)
break;
for(i=1;i<=end;i++)
        {
if(p[i]!=-1||cap[u][i]==0) continue;
            p[i] = u;
            flow[i] = min(flow[u],cap[u][i]);
            q[rear++] = i;
        }
    }
if(flow[end]==INF) return -1;
return flow[end];
}
int E_K()
{
int res=0,now,temp;
while(1)
    {
        temp=bfs();
if(temp==-1) break;
        res+=temp;
for(now=end;now!=S;now=p[now])
        {
            cap[p[now]][now]-=temp;
            cap[now][p[now]]+=temp;
        }
    }
return res;

}
int main()
{
int i,j,t,num;
while(scanf("%d%d",&M,&N)!=EOF)
    {
        S=0;end=N+1;
        memset(cap,0,sizeof(cap));
for(i=1;i<=M;i++)
        {
            scanf("%d",&room[i]);
            belong[i]=0;
        }
for(i=1;i<=N;i++)
        {
            scanf("%d",&num);
for(j=1;j<=num;j++)
            {
                scanf("%d",&t);
if(belong[t]==0)
                {
                    belong[t]=i;
                    cap[S][i]+=room[t];
                }
else cap[belong[t]][i]=INF;
            }
            scanf("%d",&t);
            cap[i][end]=t;
        }
int ans=E_K();
        printf("%d\n",ans);
    }
return 0;
}