Multiple files and classes

[sebgar]

I was trying to code an example from a book but it didn't work. Maybe because the author uses visual c and i have codeblocks? I checked word by word, looks the same.

Anyways, maybe someone can help me understand how to put this together so I can try and make it work.
There're 4 files:
file A - contains main()
file B - contains a base class (class B)
file C and D - contain derived class of B

I kept playing around with headers but always getting either one of the following erreors:
- something was declared more than once
- or something was not declared at all.

So assuming the code is good. How do put it all together (in code blocks)???

Thanks! :)