Week 02 (20)

Aside: Pointer Arithmetic (cont)

For a pointer declared as T *p; (where T is a type)

if the pointer initially contains address A
- executing p = p + k; (where k is a constant)
  - changes the value in p to A + k*sizeof(T)

The value of k can be positive or negative.

Example:

int a[6];   (addr 0x1000)       char s[10];   (addr 0x2000)
int *p;     (p == ?)           char *q;      (q == ?)
p = &a[0];  (p == 0x1000)       q = &s[0];    (q == 0x2000)
p = p + 2;  (p == 0x1008)       q++;          (q == 0x2001)