匹配 hdu 1083

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<cctype>
#include<queue>
#include<vector>
#include<algorithm>

using namespace std;
typedef long long LL;
#define N 303
#define INF 0x3f3f3f

int G[N][N], vis[N], used[N];
int n, p, x;

bool Hungary(int u)
{
    for(int i=1; i<=p; i++)
    {
        if(!vis[i]&&G[u][i])
        {
            vis[i]=1;
            if(!used[i] || Hungary(used[i]))
            {
                used[i]=u;
                return true;
            }
        }
    }
    return false;
}

int main()
{
    int T;
    scanf("%d", &T);

    while(T--)
    {
        scanf("%d%d", &p, &n);
        int num;
        memset(G, 0, sizeof(G));
        memset(used, 0, sizeof(used));
        for(int i=1; i<=p; i++)
        {
            scanf("%d", &num);
            for(int j=1; j<=num; j++)
            {
                scanf("%d", &x);
                G[x][i]=1;
            }
        }

        int ans=0;

        for(int i=1; i<=n; i++)
        {
            memset(vis, 0, sizeof(vis));
            if(Hungary(i))
                ans++;
        }
        if(ans==p)
            printf("YES\n");
        else
            printf("NO\n");
    }
    return 0;
}