: Put it with the rest of the code, then #include "header_name.h", and
: that's it. You usually don't need to include h-files in the project
: since they are never linked to binaries (unless they are written by
: a newbie). It can be convenient to include them in the project
: still, so you can open them quickly.
Well the #include<header.h> is already in the program, but when the compiler reaches that line it says headername.h file not found.