#include <iostream>

using namespace std;

class Shape
{
public:
    Shape(double w, double h) : width(w), height(h) {}
    double width;
    double height;
    virtual void hello() {cout << "hello from shape!";}
};

class SecondShape
{
public:
    SecondShape(double w, double h) : width(w), height(h) {}
    double width;
    double height;
    bool other;
    virtual void hello() {cout << "hello from shape!";}
};

class Rectangle : public Shape, public SecondShape
{
public:
    Rectangle(double w, double h) : Shape(w, h) {}
    double area() {return width * height;}
    double get_width() {return width;}
    double get_height() {return height;}
};

class Triangle : public Shape
{
public:
    Triangle(double w, double h) : Shape(w, h) {}
    double area() {return width * height / 2;}
    double get_width() {return width;}
    double get_height() {return height;}
};

class VerySpecialTriangle : public Triangle
{
public:
    VerySpecialTriangle(double w, double h) : Triangle(w, h), special(true) {}
    bool special;
    void display();
};

void VerySpecialTriangle::display()
{
    cout << "Obiekt vst:\n";
    cout << "\twysokosc: " << height << endl;
    cout << "\tszerokosc: " << width << endl;
    cout << "\tpole: " << area() << endl;
}

int main()
{
    Triangle tri(4, 3);
    Rectangle recti(10, 6);
    cout << "Obiekt recti:\n";
    cout << "\twysokosc: " << recti.get_height() << endl;
    cout << "\tszerokosc: " << recti.get_width() << endl;
    cout << "\tpole: " << recti.area() << endl;
    /*cout << "Obiekt tri:\n";
    cout << "\twysokosc: " << tri.get_height() << endl;
    cout << "\tszerokosc: " << tri.get_width() << endl;
    cout << "\tpole: " << tri.area() << endl;*/

    VerySpecialTriangle vst(10, 5);
    cout << "Obiekt vst:\n";
    cout << "\twysokosc: " << vst.get_height() << endl;
    cout << "\tszerokosc: " << vst.get_width() << endl;
    cout << "\tpole: " << vst.area() << endl;
    vst.display();

    Shape* sptr = &vst;
    sptr->hello();
    return 0;
}