Generate array of random unique numbers in PHP

php

Solution

$max = 5;
$done = false;
while(!$done){
    $numbers = range(0, $max);
    shuffle($numbers);
    $done = true;
    foreach($numbers as $key => $val){
        if($key == $val){
            $done = false;
            break;
        }
    }
}

Problem

I'm trying to generate an array of random numbers from 0-n then shuffle (but ensure that the keys and values DO NOT match). For example: ``` 0 => 3 1 => 2 2 => 4 3 => 0 4 => 1 ``` Note that both keys and values are from 0-4 but none of the keys and values are the same. Any thoughts?

Original source