Search Rotated Array ( right pointer)

Using left pointer works because by default mid pointer is rounded down
to meet with left. So we keep comparing to the left, and increment on
left.

Using right is also perfectly fine. Just make sure round up the mid
pointer ( num + divisor - 1 ) / divisor   (Note: only works if num >= 0
)

Now we can compare to the right, decrement on the right and the
algorithm would still be correct.