#include<fstream>
#include<iostream>
#include<set>

using namespace std;

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

multiset<int> s;

int main(){
    
    int n, m, x;
    fin >> n;
    
    while( n-- ){
        fin >> m;
        while( m-- ){
            fin >> x;
            s.insert(x);
        }
    }
    
    while ( s.size() ) {
        fout << *s.begin() << " ";
        s.erase(s.begin());
    }
    
    
    return 0;
}