Determining combination of bits

[Scott David Daniels]

Dennis Lee Bieber wrote:
> On Mon, 08 Nov 2004 15:33:01 -0800, Scott David Daniels
> <Scott.Daniels at Acm.Org> declaimed the following in comp.lang.python:
>>(OCA) and increment (INA)".  Note that a ones complement turns all of
>>the least significant zeros to ones, and the least significant one to
>>a zero.  When you increment that the carry propagates back to the 0 for
> 	Ones complement turns ALL 0 bits to 1, and ALL 1 bits to 0.
Right.  In particular, all of the lowest order zeroes turn to 1s,
the one directly before them turns to zero.  Those bits are the only
bits where I care what the value is, all others are simply inverted
(and it doesn't matter what values they have).

> 	00000000
> 1C	11111111	ones complement has a "negative zero"
> +1	00000000	twos complement "overflows" back to single zero

Correct, and this isoloates the least significant one bit for this value
as well (inasmuch as it doesn't exist).

--Scott David Daniels
Scott.Daniels at Acm.Org