<?xml version="1.0" encoding="windows-1252"?>
<node id="846685" title="Re: Random data generation." created="2010-06-26 12:45:07" updated="2010-06-26 12:45:07">
<type id="11">
note</type>
<author id="436161">
davies</author>
<data>
<field name="doctext">
This is actually a classic algorithm used for things like dealing a pack of cards. If you are dealing bridge hands, for example, you want 52 different cards with no repeats. Some games use multiple packs and/or cut down packs (B&amp;eacute;zique uses a pack of 2 decks, A down to 7). You therefore set up a pack with all the possible cards, deal one at random, move the last card to the position from which the card was taken &amp; reduce the pack by one. So, for your problem:&lt;c&gt;
use strict;
use warnings;

my $nRepeats = 2;
my @sSet = qw (a b c d e f);
my $nLength = 12;

my @sAll;
for (1..$nRepeats) {
	push (@sAll, @sSet);
}

if ($nLength - 1 &gt; $#sAll) {die "Don't be silly"}

my $sString;
for (1..$nLength) {
	my $i = int(rand(@sAll));
	$sString .= $sAll[$i];
	$sAll[$i] = $sAll[-1];
	pop(@sAll);
}

print "$sString \n";
&lt;/c&gt;
Now, I'm a beginner. So if anyone sees anything that could be improved (apart from Hungarian notation - it helps me conceptualise strong typing), I'd love to know.&lt;br&gt;&lt;br&gt;
Regards,&lt;br&gt;&lt;br&gt;
John Davies
&lt;br&gt;&lt;br&gt;
Update: Re-reading your question, if AABAABAABAAB is valid, my code won't do what you want, but I'm not clear on whether that's what you mean.</field>
<field name="root_node">
846630</field>
<field name="parent_node">
846630</field>
</data>
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