Message-ID:	<3892AF0D.2603ECDB@home.comNOSPAM>
From:	Robin Johnson <NOSPAMrobbat2 AT home DOT comNOSPAM>
Organization:	Orbit Computers
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Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Random numbers with rand() and srand()
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Date:	Sat, 29 Jan 2000 09:12:51 GMT
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To:	djgpp AT delorie DOT com
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"William J. Urban II" wrote:

> Hello all.  Well I am trying to generate some random "dice" rolls with rand
> and I am having difficulty.  I have #include <time.h> so that I can use
> srand(time(NULL)); to generate a new seed each time but the problem is when
> I roll a d6 for example it rolls it and will keep generating the same number
> each time the program is run.  Here is what I am talking about:
>
> #include <time.h>
>
> ~~~skipping main and stuff~~~
> int die;
>
> srand(time(NULL)); got this out of my c++ book to use the seconds to
> generate a "seed"
>
> die = ((rand%6)+1);
> die = ((rand%6)+1);
> die = ((rand%6)+1);
> die = ((rand%6)+1);
>
> when I run this each time i run it I get a different number but all four of
> them are the same.  For example...
> first run
> die = 2
> die = 2
> die = 2
> die = 2
>
> second run
> die = 5
> die = 5
> die = 5
> die = 5
>
> Could anyone help me generate more random numbers in my code?  Thanks in
> advance.
>
> Will

The problem with rand and srand is that they are not that random if the modulus
value is small,
try using random() instead


--
Robin Hugh Johnson
"Robbat2"
QTOD:"I used to be an idealist, but I got mugged by reality."
E-Mail     : robbat2 AT home DOT com
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