Pointer Arithmetic

When a pointer points to an element of an array, adding or subtracting integers moves it by that many elements, not bytes.

int arr[5] = {10,20,30,40,50};
int *p = arr;        // same as &arr[0]
printf("%d\n", *(p+2)); // -> 30

The compiler automatically scales the offset by sizeof(*p). Pointer arithmetic is only defined within the same array (or one past the last element).