Different Objects in Array

    I thought that you might find an interesting code. Perhaps, you have
seen this before. I created two classes of A and B. Two classes have
different objects. The class Obj has a relationship to class A and
class B which is called composition.
    The class Obj has one variable which is a pointer to member function
in array. You can't bind member function of both class A and class B
because they do not belong to class Obj. I use reinterpret_cast to
convert from class A to class Obj before pointer to member function is
invoked.
    I believe that my code is the alternative replacement so I don't use
inheritance and polymorphism. It is easier to extract class. What do
you think?

For example:

class A
{
public:
    A() : x( 10 ) {}
    ~A() {}

    void Run() { x++; cout << "A: " << x << endl; }

private:
    int x;
};

class B
{
public:
    B() : y( 20 ) {}
    ~B() {}

    void Run() { y++; cout << "B: " << y << endl; }

private:
    int y;
};

class Obj
{
public:
    Obj() {}
    ~Obj() {}

    void Run()
    {
        ( this->*pO[0] )();
        ( this->*pO[1] )();
    }

private:
    A a;
    B b;
    typedef void ( Obj::*To )();
    static To const pO[2];
};

Obj::To const Obj::pO[2] =
{
    reinterpret_cast< To >( &A::Run ),
    reinterpret_cast< To >( &B::Run )
};

int main()
{
    Obj o;
    o.Run();

    return 0;
}