Is the macro problem solved correctly?

Question

C++ / C#

Write a program containing macros with arguments that calculate the areas of various geometric shapes (for example, a square, a rectangle, a circle).

My decision:

#include <stdio.h>

#define SQ(a) (a) * (a)
#define REC(a,b) (a) * (b)
#define CIR(r) 3.14 * (r) * (r)

main () {
      printf("%d\n", SQ(67));
      printf("%d\n", REC(8,9));
      printf("%.2f\n", CIR(5));
}

Is it right?

Answer 1

No, not right.
For example, what do you think should be equal to 36 / SQ(6)? - Correctly think, unity.
What will your decision be? - 36.