From:	"matthew p. conte" <spam AT somebody DOT else>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Binary << ?
Date:	Wed, 18 Mar 1998 16:37:03 -0500
Organization:	little, if any
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Reply-To:	"matthew p. conte" <dont AT bother DOT com>
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

laine wrote:
>Can someone tell me how the binary << work?

All kinds of off topic, but...

<< and >> are the binary shift operators.  They shift the bits in a variable
or a number representation...

If you had an unsigned char b = 4; the bits look like this:
0 0 0 0 0 1 0 0
and you did a shift to the left by 1:
b = b<<1;  (or even better b<<=1)
the bits would now be:
0 0 0 0 1 0 0 0
making b = 8.  So just imagine that bitshifts to the left are multiplying by
powers of 2, and those to the right are dividing by powers of 2.  So:

b >>= 3;  is dividing by 2^3 or 8.

Good luck,
Matt.

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