Imagine a slot machine with 3 slots and where each slot has 3 things that could come up; A, B, or C. Each item (A,B, or C) can only come up once. (This is just for this example although sometimes it feels like that in Vegas)
Is there a way to list all of the possible combinations?
A - B - C
A - C - B
B - C - A
B - A - C
C - B - A
C - A - B
how do you store the differnet values for each "slot"? in an array?
I can do it any way that will work efficiently...An example with an array would be great.
I can think of a bunch of ways to do it that are rickety, non-scaleable, and waaaay inefficient...but there has got to be a simple way that I'm just too Monday to see right now.
after a few cup of coffee and some server errors i found a solution. it's not yet the 'best' but a start to think of how to increase the performance.
Add more values to the array just as you like to.
Attention: i didn't test it with "fixex key-value"-pairs that need to be associated! (i mean e.g. [a]=3, [d]=5 .... and the sort it)
must admit that i'm a little bit proud of that code 
$start_array = array("A", "B", "C");
function go($string, $del_array)
{
global $start_array;
if($del_array)
$new_array = array_diff($start_array,$del_array);
else
$new_array = $start_array;
if(sizeof($new_array)>0)
{
while(list($key,$val)=each($new_array))
{
$del_array[$key] = $val;
go($string." ".$val,$del_array);
$temp[] = $val;
$del_array = array_diff($del_array,$temp);
}
}
else echo "<b>".$string."</b><br>";
}
go("",false);
Just run through all combos and discard the one you don't want.
$slot1 = array('A','B','C');
$slot2 = array('A','B','C');
$slot3 = array('A','B','C');
foreach($slot1 as $r1)
{
foreach($slot2 as $r2)
{
foreach($slot3 as $r3)
{
filter($r1,$r2,$r3);
}
}
}
function filter($r1,$r2,$r3)
{
if ($r1 == $r2) return;
if ($r1 == $r3) return;
if ($r2 == $r3) return;
echo "$r1 - $r2 - $r3<br />\n";
}
What you want is generally called a "Monte Carlo" algorithm (your "Vegas" comment was closer than you thought). I doubt this link will be much use but it is kind of entertaining. Do a little more searching for Monte Carlo algorithms than I did...
You guys rock like limestone...volleytotal.ch and ahundiak, your suggestions both work beautifully. There are actually up to 6 "slots", so I'm going to play around with both solutions and see which one works for what I need. They actually gave me some great ideas to improve the rest of the project. I know it wasn't just a quick answer, so I appreciate your time...
tomhath, I forwarded your link on to my brother who is working on his PHD in Mathematics...I represent the artistic side of my family. :-)
jsut test which one of the two is the faster one!
if you do that, post the result ... i wonder who'll win
In fact, it was not an easy problem. But i really wanted to see if i can solve it scaleable. So, no wasted time and learned a lot ...
This can also be solved recursively:
<?php
permute("ABCDEF");
function permute($str, $temp="") {
if ($str == "") {
print $temp . "\n";
} else {
for ($i =0; $i<strlen($str); $i++) {
$start = $temp . substr($str, $i, 1);
$rest = substr($str, 0, $i) . substr($str, $i+1);
permute($rest, $start);
}
}
}
?>
To add/remove letters, just change the argument passed to permute and that's it.
Diego
@: nice and short solution 
guess i was too busy with thinking about using an array
Thanks ...I don't like arrays, coz it's such a hassle to use them coz u have to declare them the right size, or expand it to allocate more entries, etc...Well, I guess it's easier in PHP, but in other languages like C++ and Java it is a hassle Strings are more flexible (well, except C-string, sigh)
Diego