Courses

#include<bits/stdc++.h>
using namespace std;
#define MAXI 1005
int mp[MAXI][MAXI];
int used[MAXI];
int vis[MAXI];
int n,m,p;
bool dfs(int  x)
{
    for(int j=1;j<=p;j++)
    {
        if(mp[x][j]&&!used[j])
        {
            used[j]=1;
            if(!vis[j]||dfs(vis[j]))
              {
                  vis[j]=x;
                  return true;
              }
        }
    }
    return false;
}

int find1(void)
{    int ans=0;
 memset(vis,0,sizeof(vis));
     for(int i=1;i<=n;i++)
       {
           memset(used,0,sizeof(used));
           if(dfs(i))ans++;
       }
       return ans;
}

int main()
{
    int cas;
    scanf("%d",&cas);
    while(cas--)
    {
        memset(mp,0,sizeof(mp));
        scanf("%d%d",&p,&n);
        for(int i=1;i<=p;i++)
        {
            int k;scanf("%d",&k);
            while(k--)
            {
                int x;scanf("%d",&x);
                mp[x][i]=1;
            }
        }
        int ans=find1();
        if(ans==p)
            printf("YES\n");
        else
            printf("NO\n");
    }
}