day02

#include <memory>
#include <string> 
#include <iostream>

using salary_t = std::uint32_t;

struct user 
{
    user(const std::string &name);
    ~user();

day02

#include <iostream>
#include <string>
#include <boost/signals2.hpp>

template<typename T>
struct observable
{  
    void subscribe(const auto&& observer) 
    { 
        m_field_changed.connect(observer);

day02

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>

template<typename T>
struct observer 
{
    // callback required
    virtual void field_changed(T &source, const std::string &field_name) = 0;

day02

#include <utility>

struct MyType 
{
    [[nodiscard]] MyType() {}
};

template <typename T, typename ... Args>
[[nodiscard]] T* create(Args&& ... args)

day02

#include <iostream>
#include <memory>
#include <vector>

struct memento
{
    std::int32_t m_balance{};
    
    memento(const std::int32_t balance) : m_balance(balance) {}
};

day02

#include <iostream>
#include <vector>

struct point 
{
    int m_x{};
    int m_y{};
    
    point(const int x, const int y) : m_x(x), m_y(y){}

day02

// Example program
#include <iostream>
#include <string>
#include <cmath>

struct point
{
    struct factory 
    {
        static point cartesian(const double x, const double y) { return point(x, y); }

day02

#include <iostream>
#include <string>
#include <map>
#include <memory>

enum class point_t
{ 
    point_2D, 
    point_3D
};

day02

#include <functional>
#include <iostream>

template <typename T>
struct logger;

// return type and argument list
template <typename return_t, typename... Args>
struct logger<return_t (Args...)> 
{

day02

// Flyway Design Pattern is quite simply a space optimization technique. That allows you to use less memory by storing some of the common data to several items or several objects.

#include <boost/flyweight.hpp>
#include <string>
#include <iostream>

using namespace std;

struct user {
    user(const std::string &first_name, const std::string &last_name) : m_first_name(first_name), m_last_name(last_name) {}