up05-3(abstract factory)

#define _USE_MATH_DEFINES

#include <cmath>
#include <string>
#include <sstream>
#include <iostream>
#include <map>
#include <vector>
#include <algorithm>

class FigCreator
{
public:
    virtual Figure *create(const std::string &str) = 0;

    virtual ~FigCreator() = default;
};

class CircleCreator : public FigCreator
{
public:
    Figure *create(const std::string &str) override
    {
        return Circle::make(str);
    }

};

class RectangleCreator : public FigCreator
{
public:
    Figure *create(const std::string &str) override
    {
        return Rectangle::make(str);
    }
};

class SquareCreator : public FigCreator
{
public:
    Figure *create(const std::string &str) override
    {
        return Square::make(str);
    }
};


class AbstractFactory
{
public:

    static AbstractFactory &factory_instance()
    {
        static AbstractFactory s;
        return s;
    }

    Figure *create(const std::string &type, const std::string &params)
    {
        return disc[type]->create(params);
    }

private:
    std::map<std::string, FigCreator *> disc = {
            {"C", new CircleCreator()},
            {"S", new SquareCreator()},
            {"R", new RectangleCreator()},
    };

    AbstractFactory() = default;

    ~AbstractFactory()
    {
        for (auto &c:disc) {
            delete c.second;
        }
    }

    AbstractFactory(AbstractFactory const &) = delete;

    AbstractFactory &operator=(AbstractFactory const &) = delete;
};

int main()
{
    std::vector<Figure *> figures;
    std::string tmp;
    while (!std::getline(std::cin, tmp).eof()) {
        std::stringstream s;
        s << tmp;
        std::string type, param1, param2;
        s >> type >> param1 >> param2;
        figures.push_back(AbstractFactory::factory_instance().create(type, param1 + " " + param2));
    }

    std::stable_sort(figures.begin(), figures.end(),
            [](Figure *a, Figure *b) { return a->get_square() < b->get_square(); });

    for (auto &c:figures) {
        std::cout << c->to_string() << std::endl;
        delete c;
    }
}