#include <fstream>
using namespace std;
ifstream in("interclasari.in");
ofstream out("interclasari.out");
int v[1000005],cnt;
int main()
{
    int n,x,nr;
    in>>n;
    for(int i=1;i<=n;i++){
        in>>x;
        cnt+=x;
        for(int j=1;j<=x;j++){
            in>>nr;
            v[nr]++;
        }
    }
    in.close();
    out<<cnt<<"\n";
    for(int i=0;i<=1000000;i++)
        for(int j=1;j<=v[i];j++)
            out<<i<<" ";
    out<<"\n";
    out.close();
    return 0;
}