class와 OOP 예제2

#include <iostream>
using namespace std;

class Box {
public:

	double getVolume(void) {
		return length * breadth * height;
	}

	void setLength(double len) {
		length = len;
	}

	void setBreadth(double bre) {
		breadth = bre;
	}

	void setHeight(double hei) {
		height = hei;
	}

	// Overload + operator to add two Box objects.
	Box operator+(const Box& b) {
		Box box;
		box.length = this->length + b.length;
		box.breadth = this->breadth + b.breadth;
		box.height = this->height + b.height;
		return box;
	}

	// Overload - operator to subtract two Box objects.
	Box operator-(const Box& b) {
		Box box;
		box.length = this->length - b.length;
		box.breadth = this->breadth - b.breadth;
		box.height = this->height - b.height;
		return box;
	}

private:
	double length;      // Length of a box
	double breadth;     // Breadth of a box
	double height;      // Height of a box
};

// Main function for the program
int main() {
	Box Box1;                // Declare Box1 of type Box
	Box Box2;                // Declare Box2 of type Box
	Box Box3;                // Declare Box3 of type Box
	Box Box4;                // Declare Box3 of type Box
	double volume = 0.0;     // Store the volume of a box here

	// box 1 specification
	Box1.setLength(3.0);
	Box1.setBreadth(3.0);
	Box1.setHeight(3.0);

	// box 2 specification
	Box2.setLength(2.0);
	Box2.setBreadth(2.0);
	Box2.setHeight(2.0);

	// volume of box 1
	volume = Box1.getVolume();
	cout << "Volume of Box1 : " << volume << endl;

	// volume of box 2
	volume = Box2.getVolume();
	cout << "Volume of Box2 : " << volume << endl;

	// Add two object as follows:
	Box3 = Box1 + Box2;
	Box4 = Box1 - Box2;

	// volume of box 3
	volume = Box3.getVolume();
	cout << "Volume of Box3 : " << volume << endl;

	return 0;
}