#include <iostream>using namespace std;class A{public:	virtual void out() { cout << "Out from class A" << endl; }};class B : public A{public:	void out() { cout << "Out from Class B" << endl; }};void main(){	A a;	B b;	a.out(); // echoes "Out from class A"	b.out(); // echoes "Out from class B"	A new_a = b;	new_a.out(); // echoes "Out from class A", as expected,				// since we are _COPYING_ the parts of b 				// that are of class A over to a new object of class A	A* p_a = &b	p_a->out(); // echoes "Out from class B", because it''s a pointer				// type, and accesses the vtbl	A& r_a = b;	r_a.out(); // echoes "Out from class B", because (again) it''s a reference type (points-to)}