【HDU 5855】Less Time, More profit（网络流、最小割、最大权闭合子图）

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <queue>
#define N 205<<1
#define sf(a) scanf("%d",&a);
using namespace std;
const int INF=0x3f3f3f3f;
struct plant{
	int pay,t,id;
}pt[N];
struct shop{
	int pro,k,pt[N],t;
}s[N];
int t,n,m,l,st,ed,tot;
int arc[N][N], d[N];
int ans,tans;
bool bfs()
{
	memset(d, -1, sizeof d);
	queue<int>q;
	q.push(st);
	d[st] = 0;
	while(!q.empty())
	{
		int i,k=q.front();
		q.pop();
		for(i = 1; i <= ed; i++)
			if(arc[k][i] > 0 && d[i] == -1)
			{
				d[i] = d[k] + 1;
				q.push(i);
			}
	}
	return d[ed]>0;
}
int dinic (int k, int low)
{
	if(k == ed)return low;
	int a,i;
	for(i = 1; i <= ed; i++)
		if(d[i] == d[k] + 1&&  arc[k][i] > 0 &&(a = dinic(i, min(low, arc[k][i]))))
		{
			arc[k][i] -= a;
			arc[i][k] += a;
			return a;
		}
	return 0;
}
int cmp(plant a,plant b){
	return a.t<b.t;
}
int main() {
	sf(t);
	for(int cas=1;cas<=t;cas++){
		printf("Case #%d: ",cas);
		scanf("%d%d%d",&n,&m,&l);
		for(int i=1;i<=n;i++){
			scanf("%d%d",&pt[i].pay,&pt[i].t);
			pt[i].id=i;
		}
		for(int i=1;i<=m;i++){
			sf(s[i].pro);
			sf(s[i].k);
			s[i].t=0;
			for(int j=1;j<=s[i].k;j++){
				int x;
				sf(x);
				s[i].pt[j]=x;
				s[i].t=max(s[i].t,pt[x].t);
			}
		}
		sort(pt+1,pt+1+n,cmp);
		int ok=0;
		st=n+m+1,ed=st+1;
		for(int i=1;i<=n;i++){
			memset(arc,0,sizeof arc);
			for(int j=1;j<=i;j++)
				arc[pt[j].id][ed]=pt[j].pay;
			tot=0;
			for(int j=1;j<=m;j++)if(s[j].t<=pt[i].t){
				tot+=s[j].pro;
				arc[st][j+n]=s[j].pro;
				for(int k=1;k<=s[j].k;k++)
				arc[j+n][s[j].pt[k]]=INF;
			}
			ans = 0;
			while(bfs())
				while(tans=dinic(st, INF)) ans += tans;
			ans=tot-ans;
			if(ans>=l){
				printf("%d %d\n",pt[i].t,ans);
				ok=1;
				break;
			}
		}
		if(!ok)puts("impossible");
	}
}