How to implement classes that are related to each other?

Question

Delphi

Actually how to make connections between classes. In any case, one of the classes is not defined at the time of the description of the other.

Answer 1

Forward declaration of classes.

TUniversity = class;

TFaculty = class
private
public
  university : TUniversity;
end;

TUniversity = class
private

public 
    faculties : array of TFaculty;
end;