C++ Global variables in obj-C classes

[Achmes]

Hey,

Here's my question.

I have one header file when I have all global variables declarations.
So it looks like that:

//file variables.h

extern int var1;
extern Class1 var2;
extern Class_2 variable_3;
...

and in ".mm" file I have them definitions:

//file variables.mm
 int var1 = 0; 
Class1 var2;
 Class_2 variable_3;
...

And now is my question.
In C++ classes etc. I could just add "include variables.h", "include class1", "include class2" etc. and use this variables.

But can I do the same in obj-c classes?
Becouse I have few C++ and obj-C classes in my project and both need this variables.

Project for iPhone.