Question

How does the following pointer diagram work out in C?

Answer 1

Given the data shown above from a 16-bit system, with integer x,
unsigned integer y, and integer z, what will the following code snippet
print out?

Answer 2

@oldrin.bataku

Answer 3

int *p = &x; /* p points to the value 0x0000 at 0x0002 */
printf("%d\n", *p); /* print the value p points to (0) */
p++; /* p now points to the address 0x0004 since sizeof(int) = 2 here */
x = (int) p; /* now x's value is that address, 0x0004 */
printf("%d\n", x); /* print the value of x (0x0004) */
printf("%d\n", *p); /* p still points to the value in y at 0x0004, which is 0x0005 */
printf("%d\n", *(&(*p)));
/* *p is an alias for y, so &(*p) is equivalent to p,
and then *(&(*p)) gives the value in y, which is still 0x0005 */
printf("%d\n", *(p-1) + 1);
/* so p-1 gives the address 0x0002 again, so p-1 points to x, meaning *(p-1) gives
the value in x (0x0004) and then +1 gives 0x0005 */