include <iostream>
#include <list>
#include <iterator>
using namespace std;
void List1(list <int> g)
{
    list <int>::iterator it;
    for(it = g.begin(); it != g.end(); ++it)
        cout << '\t' << *it;
    cout << '\n';
}
int main()
{
    list <int> list1, list2;


    for (int i = 0; i < 20; ++i)
    {
        list1.push_back(i*2);
        list2.push_front(i*3);
    }
    cout << "\nList 1 (gqlist1) is : ";
    List1(list1);

    cout << "\nList 2 (gqlist2) is : ";
    List1(list2);

    cout << "\ngqlist1.front() : " << list1.front();
    cout << "\ngqlist1.back() : " << list1.back();

    cout << "\ngqlist1.pop_front() : ";
    list1.pop_front();
    List1(list1);
    return 0;

}