C Programming Tutorial

 
 
 
 
//file1.h
#define USD 1

//file2.h
#define UKP 1

//file3
#include <stdio.h>
#include <file1.h>           //A
#ifdef USD                   // B
      #define currency_rate 46     //C
#endif                    //D

#ifdef UKP               // E
#define currency_rate 100 //F
#endif                      //G
main()
{        
    int rs;
    rs = 10 * currency_rate;  //H
    printf (“%d\\n”, rs);
}

 
 
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