存边sap

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#define clear(xxx) memset(xxx,0,sizeof(xxx))
using namespace std;
const int inf=1e9;
int dis[4005],cnt[4005],n,x,y,z,m;
int N;
int tot_edge=0;
struct line{
	int from,to,remain,acc;
	int fan;
};
line edge[2000005];
int last[2005],_next[1000005];
void add_edge(int x,int y,int c,int accom){
	tot_edge++;
	edge[tot_edge].from=x;
	edge[tot_edge].to=y;
	edge[tot_edge].acc=accom;
	edge[tot_edge].remain=c;
	_next[tot_edge]=last[x];
	last[x]=tot_edge;
	tot_edge++;
	edge[tot_edge].from=y;
	edge[tot_edge].to=x;
	edge[tot_edge].acc=0;
	edge[tot_edge].remain=0;
	_next[tot_edge]=last[y];
	last[y]=tot_edge;
	edge[tot_edge].fan=tot_edge-1;
	edge[tot_edge-1].fan=tot_edge;
}
int sap(int u,int flow){
	int v,temp,delta=0;
	if(u==N+2)return flow;
	for(int h=last[u];h;h=_next[h]){
		v=edge[h].to;
		if(edge[h].remain&&dis[u]==dis[v]+1){
			temp=sap(v,min(flow-delta,edge[h].remain));
			edge[h].remain-=temp;
			edge[edge[h].fan].remain+=temp;
			delta+=temp;
			if(delta==flow||dis[N+1]>=N+2)return delta;
		}
	}
	if(dis[N+1]>N+2)return delta;
	cnt[dis[u]]--;
	if(cnt[dis[u]]==0)dis[N+1]=N+2;
	dis[u]++;
	cnt[dis[u]]++;
	return delta;
}
int main(){
	int tot=0,i,j,k,t=0,t3,t4;
	cin>>n>>m;
	N=n+m;
	for(i=1;i<=n;i++){
		add_edge(i+m,N+2,1,1);
		int x;
		while(scanf("%d",&x)!=EOF&&x!=0){
			add_edge(x,m+i,1,1);
		}
	}
	for(i=1;i<=m;i++)add_edge(N+1,i,1,1);
	while(dis[N+1]<N+2){
		t+=sap(N+1,inf);
	}
	cout<<t;
}