Here is a list of file names with extensions. Pick at least one that could properly be the implementation file and at least one that can properly serve as interface file.

Question

a) File.cxx
b) File.hxx
c) File.cc
d) File.h
e) File.cpp
f) File.hpp

Answer 1

Implementation: parts a) c) and e); interface parts b) d) and f).
Explanation: Parts a), c) and e) have extensions that systems recognize as C++ source files, hence could serve implementation. b) d) and f) have extensions that are used bycompiler writers and systems as header files. Compiler don't care much what the
extension is for #include files. (The #include directive isn’t very smart.)
Note that hxx and hpp are not mentioned in the text.