Prove that, if x AND x-1 = 0 then x=2^m (m>=0).

From: Srinu <sinu.nayak2001@xxxxxxxxx>
Date: Sun, 21 Oct 2007 11:17:03 -0000

Hi all,

How to prove, if x AND x-1 = 0 then x=2^m (m>=0)?

Here the fact is, if we perform a logical AND operation of the bits of
x and x-1 (x and x-1 are two numbers stored in computer memory) and we
get a value zero, then we can say x is a number that is power of 2.

Srinu.

.

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