Question

This is a normal C routine program which i found out in some question bank. It is shown below:

#define CUBE(p) p*p*p

main()
{
    int k;
    k = 27 / CUBE(3);
    printf("%d", k);
}

As per my understanding and knowledge the value of K should be 1 as CUBE(3) would be replaced by 3*3*3 during preprocessing and after the subsequent compilation it would be giving the value of 1, but instead it has shown the value of 81 which has made me curious to know how it happened.

Can anyone please justify the answer of 81 to this question above.

Answer 1

Preprocessors should be parenthesized properly. Replace it with

#define CUBE(p) ((p)*(p)*(p))

and see.