From:	<scochran AT shoalsnet DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Fast random number generator
Date:	15 Jul 1997 03:09:16 GMT
Organization:	CICNet Chicago server 2
Lines:	47
Message-ID:	<01bc90cc$81dffec0$d1488cd0@scochran.SHOALSnet.com>
References:	<33C91424 DOT 7615 AT wanadoo DOT fr>
NNTP-Posting-Host:	208.140.72.209
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Alan Poppleton <Alan DOT Poppleton AT wanadoo DOT fr> wrote in article
<33C91424 DOT 7615 AT wanadoo DOT fr>...
> I need a fast and simple algorithm which can produce a fairly random 
> number given two seeds - x and y.  Any ideas?  It MUST be SIMPLE and 
> FAST and it only needs to return a number between 0 and 15.

okay.. Why don't you use standard C.  It might be faster to use like chaos
or list of random numbers.  I haven't looked into it but this should work
good for most applications.

/*CODE*/
#include <stdlib.h>
#include <time.h>

void randomxy( int&, int&);

int main(void)
{
int foox, fooy;

srandom(time(NULL));

randomxy(foox, fooy);

return 0;
}

void randomxy(int &x, int &y) // using refrences speeds it up by using the
actual varibles
{
 int r = random(225);
 x = r / 15;
 y = r % 15;
} 

/*End of CODE*/

There you are.  I'm pretty sure it works, and it produces fairly
random numbers.  If you want speed you'll just have to use
read a list of randomized numbers.

Micah Cochran
scochran AT shoalsnet DOT com

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