Quick introduction to macros

main.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define SIZE 8
#define PRODUCT(X, Y) (X) * (Y)

int main(int argc, char* argv[]) {

    int arr[SIZE];
    int i;
    for (i = 0; i < SIZE; i++) {
        arr[i] = 12;
    }

    int a = 2, b = 6;
    printf("%d\n", PRODUCT(a + 1, b));
    return 0;
}