std::priority_queue

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

template<typename T>
void pop_println(std::string_view rem, T& pq)
{
    std::cout << rem << ": ";
    for (; !pq.empty(); pq.pop())
        std::cout << pq.top() << ' ';
    std::cout << '\n';
}

template<typename T>
void println(std::string_view rem, const T& v)
{
    std::cout << rem << ": ";
    for (const auto& e : v)
        std::cout << e << ' ';
    std::cout << '\n';
}

int main()
{
    const auto data = {1, 8, 5, 6, 3, 4, 0, 9, 7, 2};
    println("datos", data);

    std::priority_queue<int> max_priority_queue;

    // Poblar la cola de prioridad.
    for (int n : data)
        max_priority_queue.push(n);

    pop_println("max_priority_queue", max_priority_queue);

    // std::greater<int> hace que la cola de prioridad con
    // montculo de mximos acte como una cola de prioridad
    // con montculo de mnimos.
    std::priority_queue<int, std::vector<int>, std::greater<int>>
        min_priority_queue1(data.begin(), data.end());

    pop_println("min_priority_queue1", min_priority_queue1);

    // Segunda manera de definir una cola de prioridad
    // con montculo de mnimos.
    std::priority_queue min_priority_queue2(data.begin(), data.end(), std::greater<int>());

    pop_println("min_priority_queue2", min_priority_queue2);

    // Usando un objeto funcin personalizado para comparar elementos.
    struct
    {
        bool operator()(const int l, const int r) const { return l > r; }
    } customLess;

    std::priority_queue custom_priority_queue(data.begin(), data.end(), customLess);

    pop_println("custom_priority_queue", custom_priority_queue);

    // Usando una lambda para comparar elementos.
    auto cmp = [](int left, int right) { return (left ^ 1) < (right ^ 1); };
    std::priority_queue<int, std::vector<int>, decltype(cmp)> lambda_priority_queue(cmp);

    for (int n : data)
        lambda_priority_queue.push(n);

    pop_println("lambda_priority_queue", lambda_priority_queue);
}