#include <iostream>
#include <queue>
#include <set>

int main() {
    const std::set<int> unique{4, 2, 4, 1};
    std::queue<int> work{};
    work.push(2);
    work.push(5);
    std::cout << "unique\n";
    for (const int value : unique) {
        std::cout << value << '\n';
    }
    std::cout << "queue\n";
    while (!work.empty()) {
        std::cout << work.front() << '\n';
        work.pop();
    }
    std::cout << "empty " << work.empty() << '\n';
    return 0;
}