#include <fstream>
using namespace std;
ifstream f("interclasari.in");
ofstream g("interclasari.out");
int a[20][1000001],n,b[20000000],l=0;

int main()
{
    int i,j;
    f >> n;
    for (i=0; i<n; i++)
    {
        f >> a[i][0];
        l+=a[i][0];
        for (j=1; j<=a[i][0]; j++)
        {
            f >> a[i][j];
        }
    }
    int max, p;
    for (i=0; i<l; i++)
    {
        max=-1;
        for (j=0; j<n; j++)
        {
            if (a[j][0] && max<a[j][a[j][0]]) max=a[j][a[j][0]] , p = j;
        }
        b[i]=max;
        a[p][0]--;
    }
    g << l << endl;
    for (i=l-1; i>=0; i--)
    {
        g << b[i] << " ";
    }
}