class prop
{
public:
	prop(): var_int( 3 ), public_var(var_int), protected_var(var_int)
	{}
public:
	const int &public_var;
protected:
	int &protected_var;
private:
	int var_int;
};

void main(void)
{
	prop the_prop;
//	the_prop.public_var =  10 ;
//	the_prop.protected_var =  20 ;
	cout << the_prop.public_var << endl;
}

class property_owner;
class derived_owner;
template <class T>
class property
{
public:
	property(){};
	property(T newT): prop_value(newT){}

	operator T () const
	{return prop_value;}

protected:
	property &operator=(const T newT)
	{prop_value=newT; return (*this);}
	
	friend property_owner;
	friend derived_owner;
private:
	T prop_value;
};
class property_owner
{
public:
	property<int> val;
};
class derived_owner: public property_owner
{
public:
	derived_owner()
	{val =  30 ;}

};
void main(void)
{
	property_owner the_owner;

	cout << the_owner.val << endl;

	derived_owner the_owner2;

	cout << the_owner2.val << endl;
}