bzoj1711: [Usaco2007 Open]Dining吃饭

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
#define rep(i,n) for(int i=1;i<=n;i++)
#define clr(x,c) memset(x,c,sizeof(x))
#define qwq(x) for(edge *o=head[x];o;o=o->next)
const int nmax=505;
const int maxn=40005;
const int inf=0x7f7f7f7f;
int read(){
	int x=0;char c=getchar();bool f=true;
	while(!isdigit(c)){
		if(c==‘-‘) f=false;c=getchar();
	}
	while(isdigit(c)) x=x*10+c-‘0‘,c=getchar();
	return f?x:-x;
}
struct edge{
	int to,cap;edge *next,*rev;
};
edge edges[maxn],*pt,*head[nmax],*cur[nmax],*p[nmax];
void add(int u,int v,int w){
	pt->to=v;pt->cap=w;pt->next=head[u];head[u]=pt++;
}
void adde(int u,int v,int w){
	add(u,v,w);add(v,u,0);head[u]->rev=head[v];head[v]->rev=head[u];
}
int cnt[nmax],h[nmax];
int maxflow(int s,int t,int n){
	clr(cnt,0);cnt[0]=n;clr(h,0);
	int flow=0,a=inf,x=s;edge *e;
	while(h[s]<n){
		for(e=cur[x];e;e=e->next) if(e->cap>0&&h[x]==h[e->to]+1) break;
		if(e){
			p[e->to]=cur[x]=e;a=min(a,e->cap);x=e->to;
			if(x==t){
				while(x!=s) p[x]->cap-=a,p[x]->rev->cap+=a,x=p[x]->rev->to;
				flow+=a,a=inf;
			}
		}else{
			if(!--cnt[h[x]]) break;
			h[x]=n;
			for(e=head[x];e;e=e->next) if(e->cap>0&&h[x]>h[e->to]+1) cur[x]=e,h[x]=h[e->to]+1;
			cnt[h[x]]++;
			if(x!=s) x=p[x]->rev->to;
		}
	}
	return flow;
}
int main(){
	pt=edges;clr(head,0);
	int n=read(),F=read(),D=read(),u,v,s=0,t=F+D+n+n+1;
	rep(i,n){
		adde(F+i,F+n+i,1);
		u=read(),v=read();
		rep(j,u) adde(read(),F+i,1);
		rep(j,v) adde(F+n+i,F+n+n+read(),1);
	}
	rep(i,F) adde(s,i,1);
	rep(i,D) adde(F+n+n+i,t,1);
	printf("%d\n",maxflow(s,t,t+1));
	return 0;
}