#include <iostream>
using namespace std;
int main ()
{
    int N, K, P[10], u[10][20], uch[10]={0}, br=0, br2=0, max, maxn, i, j, k=0;
    bool umnuzh[20]={0};
    cin>>N>>K;
    for (i=0;i<N;i++)
    {
        cin>>P[i];
        for (j=0;j<P[i];j++)
            cin>>u[i][j];
    }
    do {max=0;br2=0;maxn=0;
        for (i=0;i<N;i++)
        {
            br=0;
            for (j=0;j<P[i];j++)
                if (umnuzh[u[i][j]]==0) br++;
            if (br>max) {max=br;maxn=i;}
        }
        uch[k]=maxn;k++;
        for (i=0;i<P[maxn];i++)
            umnuzh[u[maxn][i]]=1;
       }
    while (max>0);
    cout<<k-1<<endl;
    sort (uch, uch+(k-1));
    for (i=0;i<k-2;i++)
        cout<<uch[i]+1<<" ";
    cout<<uch[k-2]+1<<endl;
    return 0;
}
