// Illustrates the use of virtual functions

#include <iostream.h>

class base {
    public:
	void a(void) { cout << "base::a called\n"; }
	virtual void b(void) { cout << "base::b called\n"; }
	virtual void c(void) { cout << "base::c called\n"; }
};

class derived: public base {
    public:
	void a(void) { cout << "derived::a called\n"; }
	void b(void) { cout << "derived::b called\n"; }
};

void do_base(base &a_base)
{
    cout << "Call functions in the base class\n";

    a_base.a();
    a_base.b();
    a_base.c();
}

main()
{
    derived a_derived;

    cout << "Calling functions in the derived class\n";

    a_derived.a();
    a_derived.b();
    a_derived.c();

    do_base(a_derived);
    return (0);
}