#include <bits/stdc++.h>

using namespace std;

ifstream fin("interclasari.in");
ofstream fout("interclasari.out");

int K, N, x, Ans;
set < int > S;

int main()
{
    fin >> K;
    for (int i = 1; i <= K; i++) {
        fin >> N;
        for (int j = 1; j <= N; j++) {
            fin >> x;
            S.insert(x);
        }
        Ans += N;
    }
    fout << Ans << "\n";
    for (auto it: S) {
        fout << it << " ";
    }
    return 0;
}