Hi, I have been pulling my hair out yesterday and today trying to figure out why this little bit of code wont give me a unique random number. can anyone enlighten me PLEASE <img src=../images/dmxzone/forum/icon_smile_sad.gif border=0 align=middle>

numbers is an array to store the unique random numbers (kind of like lottery numbers). it all works OK (except for not giving unique numbers) I think the while loop is the problem, but not sure why??????


for ($i=0 ; $i&lt;11; $i++)
{
$rand = rand(0,10);
for( $y = 0 ; $y &lt;11; $y++){
while ($rand == $numbers[$y])
{
$rand = rand(0,10);
}
}
$numbers[$i] = $rand;
}

thank you very much in advance
sue

sue--

Simple logic mistake. Your while loop needs to be on the outside of the foor loop. Think of it this way:

WHILE the number is still not unique:
FOR each number:
check if it matches that number

Like so:

<pre id=code><font face=courier size=2 id=code>
for ($i=0;$i&lt;11;$i&#43;&#43; ){
$done=false;
while(!$done){
$rand=rand(0,10);
$done=true;
for($y=0;$y&lt;count($numbers);$y&#43;&#43; ){
if($rand==$numbers[$y])
$done=false;
}
}
$numbers[$i] = $rand;
}
</font id=code></pre id=code>

Demo page here: http://www.andrewpeace.com/unique-random-numbers.php

Andrew Peace - Like my posts? You'll love my site