SimpleClassHierarchy

#include <iostream>
#include <vector>

class mainClassPlanes { //Main Class
public:
    mainClassPlanes(const std::string& planeName, const std::string& originCountry, int originYear)
        : planeName(planeName), originCountry(originCountry), originYear(originYear){}
    virtual ~mainClassPlanes() {} //destructor
    virtual void displayInfo() const = 0;
protected:
    std::string planeName;
    std::string originCountry;
    int originYear;
};
class ww2Planes : public mainClassPlanes { //WW2 Class derived from Main Class
public:
    ww2Planes(const std::string& planeName, const std::string& originCountry, int originYear, const std::string& alliance, int numberBuilt, int planeSeats)
        : alliance(alliance), numberBuilt(numberBuilt), planeSeats(planeSeats), mainClassPlanes(planeName, originCountry, originYear){}
    virtual void displayInfo() const override {
        std::cout << "Plane name: " << planeName << std::endl;
        std::cout << "Country of origin: " << originCountry << std::endl;
        std::cout << "Year of origin: " << originYear << std::endl;
        std::cout << "Alliance: " << alliance << std::endl;
        std::cout << "Number built: " << numberBuilt << std::endl;
        std::cout << "Plane seats: " << planeSeats << std::endl;
    }; //display
protected:
    std::string alliance;
    int numberBuilt;
    int planeSeats;
};
class ww1Planes : public mainClassPlanes { //WW1 Class derived from Main Class
public:
    ww1Planes(const std::string& planeName, const std::string& originCountry, int originYear, const std::string& alliance, int numberBuilt, float size)
        : alliance(alliance), numberBuilt(numberBuilt), size(size), mainClassPlanes(planeName, originCountry, originYear){}
    virtual void displayInfo() const override {
        std::cout << "Plane name: " << planeName << std::endl;
        std::cout << "Country of origin " << originCountry << std::endl;
        std::cout << "Year of origin: " << originYear << std::endl;
        std::cout << "Alliance: " << alliance << std::endl;
        std::cout << "Number built: " << numberBuilt << std::endl;
        std::cout << "Plane size: " << size << " meters" << std::endl;
    }; //display
protected:
    std::string alliance;
    int numberBuilt;
    float size;
};

int main()
{
    ww2Planes bf109("Messerschmitt Bf 109", "Nazi Germany", 1937, "Axis", 34248, 2);
    ww2Planes yak9("Yakovlev Yak-9", "Soviet Union", 1942, "Allies", 16769, 1);
    ww1Planes fokkerDVII("Fokker D.VII", "Germany", 1918, "Central Powers", 3300, 6.95);
    ww1Planes bristolF2("Bristol F.2", "United Kingdom", 1916, "Entente Powers", 5329, 7.87);
    std::vector<std::shared_ptr<mainClassPlanes>> planes;
    planes.push_back(std::make_shared<ww2Planes>(bf109));
    planes.push_back(std::make_shared<ww2Planes>(yak9));
    planes.push_back(std::make_shared<ww1Planes>(fokkerDVII));
    planes.push_back(std::make_shared<ww1Planes>(bristolF2));

    for (const auto& mainClassPlanes : planes)
    {
        mainClassPlanes->displayInfo();
        std::cout << "-------------------------------------" << std::endl;
    }
    return 0;
}