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Date: Fri, 7 Sep 2007 21:07:08 -0400
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From: DJ Delorie <dj AT delorie DOT com>
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In-reply-to: <60s3e31ouck81u9ti1njogqcoj1a5tfta3@4ax.com> (message from Brian
	Inglis on Sat, 08 Sep 2007 00:45:58 GMT)
Subject: Re: random() : What am I doing wrong?
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> IIRC the best distributed approach is to take a sufficient number of
> bits b around the middle of the random integer, shift right to give you
> a set 0..2^b-1 and if the number is bigger than you can use, try again
> with a new random integer. 

If you use random(), it's already pulling bits out of the middle of
its state machine.

But the odds of needing to call random() twice are much lower if you
check for the 49 values from 2,147,483,600 to 2,147,483,647, and use
'%' to scale the remaining range.