求一个指定范围内多个不重复随机数~

<?php function unique_random(& $result, $size=6, $min=0, $max=500){    $num = mt_rand($min, $max);    !in_array($num, $result) && array_push($result, $num);        return count($result) >= $size ? $result : unique_random($result, $size, $min, $max);}$result = array();unique_random($result);print_r($result);

Array(    [0] => 132    [1] => 351    [2] => 43    [3] => 425    [4] => 449    [5] => 269)

$arr = array();for($i=1;$i<=500; $i++){    array_push($arr, $i);}shuffle($arr);$ret = array_slice($arr, 0, 6);print_r($ret);