#include <iostream> // includes standard input/output functions

using namespace std; // allows access to hidden names like cout, cin

//Declaration
class Circle  
{
public:
  Circle(int num);
  Circle(double r, int num);
  void SetRadius(double r); 
  double AreaOf();         
  const int my_num;          // index of circle
private:
  double radius;             // radius of circle
};

//Definition (Implementation):

Circle::Circle(int num):radius(1), my_num(num)
{
  cout<<"Circle "<<my_num<<" is here! Radius = "<<radius<<endl;
}

Circle::Circle(double r, int num):radius(r), my_num(num)
{
  cout<<"Circle "<<my_num<<" is here! Radius = "<<radius<<endl; 
}

void Circle::SetRadius(double r)
{
  radius = r; //radius refers to this object’s Circle::radius
}

double Circle::AreaOf()
{
  return (3.14*radius*radius);
}

int main()
{
  Circle C1(0);
  Circle C2(11.5, 1);

  return 0;
}

/* try:
   initializing my_num in constructor
   changing my_num from main()
   calling default constructor
*/