algoritmo bubblesort

[ifts2004]

<?php 
$arr = array(2,4,1,66,12);

function ordina ( $arr )  {
    global $arr;
    for ( $i = 1; $i<count($arr); $i++){
        for ( $j = 0; $j<count($arr)-1; $j++){
        if ( $arr[j]> $arr[i]){
            $arr[i] = $temp;
            $arr[j] = $arr[i];
            $arr[j] = $temp;
        }
    }
    }

    $ris =  print_r($arr);
    echo $ris;
}




ordina ($arr);


 } ?>

Perchè mi stampa

Array ( [0] => 2 [1] => 4 [2] => 1 [3] => 66 [4] => 12 ) 1