#include <stdio.h>

#define Project1                    0x0                
#define PROTECT_VERION                Project1

int main()
{
    int i;
    
#if((PROTECT_VERION == Project2) || (PROTECT_VERION == Project3))
    i = 3000;                                //        384        電池額定容量，單位100mAh
#elif(PROTECT_VERION == Project1)
    i = 2000;                                //        384        電池額定容量，單位100mAh
#else
    i = 1720;                                //        384        電池額定容量，單位100mAh
#endif            
    
    printf("Hello, World!\n");
    printf("i = %d\n", i);

    return 0;
}

$gcc -o main *.c

$main

Hello, World!
i = 3000