C++ 継承練習

main.cpp

/*
https://rinatz.github.io/cpp-book/ch07-03-inheritance/
*/

#include <iostream>

class Rectangle {
 public:
    Rectangle(int h, int w): height_(h), width_(h) {};
    int Area() const {
       return height_ * width_;
    }

    int height_;
    int width_;
};

class Square : public Rectangle {
 public:
    Square(int size) : Rectangle(size, size){}
};

int calcArea(Rectangle rect){
	int h = rect.width_;
	int w = rect.height_;
	std::cout << "calcArea for Rectangle ";
	return h * w;
}

int calcArea(Square rect){
	int h = rect.width_;
	std::cout << "calcArea for Square ";
	return h * h;
}

int main() {
	Rectangle r(10, 5);
    Square s(20);
    std::cout << r.Area() << std::endl;
    std::cout << calcArea(r) << std::endl;
    std::cout << s.Area() << std::endl;
    std::cout << calcArea(s) << std::endl;
    return 0;
}