Code for Example of using preprocessor - 2 in different files in C Programming
//file1.h#define USD 1
//file2.h#define UKP 1
//file3
#include <stdio.h>
#include <file1.h> //A#if (defined (USD)) // B #define currency_rate 46
#else#define currency_rate 100 //C#endif//D
main()
{
int rs;
rs = 10 * currency_rate; //H
printf (“%d\n”, rs);
}