POJ 1274 The Perfect Stall

#include <cstdio>
#include <cstring>
#include <iostream>
using namespace std;
#define MAX 210
int g[MAX][MAX],vis[MAX],link[MAX];
int n,m;
int dfs(int x){
    for(int i = 1;i <= m;i++){
        if(g[x][i] && vis[i] == 0){
            vis[i] = 1;
            if(link[i] == -1 || dfs(link[i])){
                link[i] = x;
                return 1;
            }
        }
    }
    return 0;
}
int main(){
    while(~scanf("%d%d",&n,&m)){
        int x,xx;
        memset(g,0,sizeof(g));
        memset(link,-1,sizeof(link));
        for(int i = 1;i <= n;i++){
            scanf("%d",&x);
            for(int j = 1;j <= x;j++){
                scanf("%d",&xx);
                g[i][xx] = 1;
            }
        }
        int ans = 0;
        for(int i = 1;i <= n;i++){
            memset(vis,0,sizeof(vis));
            if(dfs(i)) ans++;
        }
        cout<<ans<<endl;
    }
    return 0;
}