Relationships between large project classes (objects) and project objects

Relationships between large project classes (objects) and project objects

Think about one question:

Interaction between classes (objects. The "brain" of the human body controls each <part> of the body, and the perception of each <part>
Return to <brain>.
<Brain> and <part> are considered as two classes (objects)
<Brain> and <part> are both a whole <person>
<Person> is a whole project)
: In this case, no matter how large the project is, all the public data variables required for each <part> can be declared in the header file of <persons>.
You can also define a header file separately and then reference this header file in the header file of <person>. Then, each <part>
Can be used.