Subj : Re: bit shifting
To   : comp.programming
From : Willem
Date : Sun Aug 14 2005 08:20 pm

Rob wrote:
) My apologies for not getting all of this too quickly - I do feel like a bit
) of a dope.  Anyway, I *think* I understand, so lets see if what I think is
) happening, is really happening.
)
) On paper, if I write down the number 128(decimal) in binary, it would look
) like this:  10000000
)
) On paper, if I write down the number 127(decimal) in binary, it would look
) like this: 1111111
)
) On paper, if I take 10000000 and do a complement operation on it, I get
) this:  01111111
)
) But, on my computer,I am thinking 128 binary might look something more like
) this:  000...010000000, so that when I perform a complement operation on
) it, all the bits *before* the 1 and *after* get flipped, like so: 
) 111...101111111.  Does that make sense, and I am correct?

You've almost got it.  A variable has a very specific number of bits,
and the ~ operator flips every one of them.

shorts usually have 16 bits nowadays.  You want 'char' for 8 bits.

So, a 'short' value of 128 (decimal) would be 0000000010000000 binary.


SaSW, Willem
-- 
Disclaimer: I am in no way responsible for any of the statements
            made in the above text. For all I know I might be
            drugged or something..
            No I'm not paranoid. You all think I'm paranoid, don't you !
#EOT

.