Write a function to sort an array

<?php
function array_sort($a)
{
 for($x=0;$x< count($a);++$x)
  {
    $min = $x;
  for($y=$x+1;$y< count($a);++$y)
   {
	 if($a[$y] < $a[$min] ) 
	 {
	   $temp = $a[$min];
	   $a[$min] = $a[$y];
	   $a[$y] = $temp;
	 }
	}
  }
 return $a;
 }
$a = array(51,14,1,21,'hj');
print_r(array_sort($a));
?>

Sample Output:

Array                                                       
(                                                           
    [0] => hj                                               
    [1] => 1                                                
    [2] => 14                                               
    [3] => 21                                               
    [4] => 51                                               
)