#include

  #include (directive)

Treats text in the file specified by filename as if it appeared in the
current file.

 Syntax:

   #include "filename"
   #include <filename>

 #include "filename" searches the source path first, then the include path.

 #include <filename> does not search the source directory.

 Examples:
  #include <stdio.h>
  #include "main.h"

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