>>626
class B { virtual void age() = 0; };
class B1 : public B { void age() { fusianasan(); } };
class B2 : public B { void age() { mokorimoko(); } };
class A
{
B* sage;
void proc() { sage->age(); }
};
class A1 : public A { A1() { sage = new B1; } };
class A2 : public A { A2() { sage = new B2; } };