#include <iostream>
#include <queue>
#include <vector>
#include <functional>

using namespace std;

template<typename T, template<class> class Compare = std::less, template<class, class> class Container = std::vector>
std::priority_queue<T, Container<T, std::allocator<T>>, Compare<T>>
make_pqueue()
{
    return std::priority_queue<T, Container<T, std::allocator<T>>, Compare<T>>();
}

int main() {
    int arr[] = {5, 3, 4, 2, 1};
    size_t size = sizeof(arr) / sizeof(*arr);

    auto pqueue = make_pqueue<int,greater>();

    for(size_t i = 0; i < size; ++i) {
        pqueue.push(arr[i]);
    }

    while (!pqueue.empty()) {
        cout << pqueue.top() << endl;
        pqueue.pop();
    }
}