Pointer subtraction

/* 1602.c: Pointer subtraction */
#include <stdio.h>

main()
{
    int *ptr_int1, *ptr_int2, i;

    printf("The position of ptr_int1: 0x%p\n", ptr_int1);
    ptr_int2 = ptr_int1 + 5;
    printf("The position of ptr_int2 = ptr_int1 + 5: 0x%p\n", ptr_int2);
    printf("The subtraction of ptr_int2 - ptr_int1: %d\n", ptr_int2 - ptr_int1);
    ptr_int2 = ptr_int1 - 5;
    printf("The position of ptr_int2 = ptr_int1 - 5: 0x%p\n", ptr_int2);
    printf("The subtraction of ptr_int2 - ptr_int1: %d\n", ptr_int2 - ptr_int1);

    return 0;
}