#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("interclasari.in");
ofstream fout("interclasari.out");
int k,n,v[20000001],m;
int main()
{
    fin>>k;
    for(int i=1;i<=k;i++)
    {
        fin>>n;
        for(int i=1;i<=n;i++)
        {
            fin>>v[i+m];
        }
        m+=n;
    }
    sort(v+1,v+m+1);
    fout<<m<<"\n";
    for(int i=1;i<=m;i++)
    {
        fout<<v[i]<<" ";
    }

    return 0;
}