Class name does not name a type in C++

Question

I just started programming in C++, and I\'ve tried to create 2 classes where one will contain the other.

File A.h:

#ifndef _A_h
#define          


        

Answer 1

It actually happend to me because I mistakenly named the source file "something.c" instead of "something.cpp". I hope this helps someone who has the same error.