#include <iostream>
#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream f ("interclasari.in");
ofstream g ("interclasari.out");
int i,j,m,n,v[20000000],a,k,x;
int main()
{
    f>>n;
    a=0;
    for (i=1;i<=n;i++)
    {
        f>>k;
        for (j=1;j<=k;j++){
           f>>x;
           a++;
           v[a]=x;}







    }
    g<<a<<'\n';
    sort(v+1,v+a+1);
    for (i=1;i<=a;i++)
            g<<v[i]<<" ";
    return 0;
}