#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <algorithm>

using namespace std;

const int Nmax = 1000002;
const int Kmax = 22;

typedef pair<int,int> node;

#define first val
#define second ind

vector <int> G;



int N, K, Sum;

void read()
{
    ifstream f("interclasari.in");

    f >> K;

    for ( int i = 1; i <= K; ++i )
    {
        f >> N;

        for ( int j = 1, elem; j <= N; ++j )
                f >> elem,
                G.push_back( elem );

        Sum += N;
    }

    f.close();
}

void print()
{
    ofstream g("interclasari.out");

    g << Sum << "\n";

    for ( unsigned i = 0; i < Sum; ++i )
            g << G[i] << " ";

    g << "\n";
}

int main()
{
    read();
    sort( G.begin(), G.end() );
    print();

    return 0;
}