#include <stdio.h>

#define TOSTRING2(x) #x
#define TOSTRING(x) TOSTRING2(x)

#define HALF(n) n / 2

int main(void)
{
    int n = 8;
    printf("Let's see what half of n + 2 is: %s\n", TOSTRING(HALF(n + 2)));
    return 0;
} 

Let's see what half of n + 2 is: n + 2 / 2