Factory pattern implementation in c++

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#include <stdexcept>
#include <iostream>
#include <memory>

class Pizza {
public:
    virtual int getPrice() const = 0;
};

class HamAndMushroomPizza : public Pizza {
public:
    virtual int getPrice() const { return 850; }
};


class DeluxePizza : public Pizza {
public:
    virtual int getPrice() const { return 1050; }
};

class HawaiianPizza : public Pizza {
public:
    virtual int getPrice() const { return 1150; }
};

class PizzaFactory {
public:
    enum PizzaType {
        HamMushroom,
        Deluxe,
        Hawaiian
    };

    static Pizza* createPizza(PizzaType pizzaType) {
        switch (pizzaType) {
        case HamMushroom:
            return new HamAndMushroomPizza();
        case Deluxe:
            return new DeluxePizza();
        case Hawaiian:
            return new HawaiianPizza();
        }
        throw "invalid pizza type.";
    }
};

/*

* Create all available pizzas and print their prices
*/

void pizza_information( PizzaFactory::PizzaType pizzatype )
{
    Pizza* pizza = PizzaFactory::createPizza(pizzatype);
    std::cout << "Price of " << pizzatype << " is " << pizza->getPrice() << std::endl;
    delete pizza;
}

int main ()
{
    pizza_information( PizzaFactory::HamMushroom );
    pizza_information( PizzaFactory::Deluxe );
    pizza_information( PizzaFactory::Hawaiian );
}