What's the best way to create a n array of classes?

[Ey80oG1T]

So I have two classes, A and B. And I want to create an array of A in B. What's the best way to do this?

Should I just create an array normally like this:

class A
{
private:
  int x, y;

public:
  void DoSomething();
};

class B
{
private:
  vector<A> arr;
};

Or could I have a nested class like so:

class B
{
private:
  class A {};

  vector<A> arr;
};

Or perhaps some other method? Thanks.

[keskiverto]

Who cares? Yes indeed, who needs to know about A?

If the answer is "nobody, but B", then you could go one step further and use pimpl idiom. See https://en.cppreference.com/w/cpp/language/pimpl