очередь на ОЛС

#include <iostream>
#include <string>
using namespace std;

struct Queue
{
    int info;
    Queue *next;
};

void Push(Queue *&first, Queue *&last, int info)
{
    Queue *newElem = new Queue;
    newElem->info = info;
    newElem->next = NULL;
    if (first != NULL)
        last = last->next = newElem;
    else
        first = last = newElem;
}

int Pop(Queue *&first, Queue *&last)
{
    Queue *tmp = first;
    first = first->next;
    int result = tmp->info;
    delete tmp;
    if (first == NULL)
        last = NULL;
    return result;
}

int main()
{
    Queue *qFirst = NULL, *qLast = NULL;
    string command;
    int number;

    setlocale(LC_ALL, "rus");
    cout << "Вводите команды управления очередью (признак окончания ввода - END):\n";
    while (true)
    {
        cin >> command;
        if (command == "END")
            break;
        else if (command == "PUSH")
        {
            cin >> number;
            Push(qFirst, qLast, number);
        }
        else if (command == "POP")
            Pop(qFirst, qLast);
        else
            cout << "Такой команды нет!\n";
    };

    cout << "В очереди осталось: ";
    while (qFirst != NULL)
        cout << Pop(qFirst, qLast) << ' ';
    cout << endl;
    system("pause");
    return 0;
}