text: #include <iostream>
  
  using namespace std;
  
  class Rectangle {
  		int width,height;//intance var
  	public:
  	Rectangle(){//default constructor
  		width=0;
  		height=0;
  	}
  	Rectangle(int w,int h){//default constructor
  		width=w;
  		height=h;
  	}
  		void set_value(int, int);
  		int area (void);
  }rect1;
  
  void Rectangle::set_value(int w, int h){
  	width = w;
  	height =h;
  }
  
  int Rectangle::area(){
  	return width*height;
  }
  
  int main(){
  	rect1.set_value(1,2);
  	Rectangle rect2(4,8);
  	cout << rect1.area() << endl;
  	cout << rect2.area() << endl;
  	return 0;
  }
  