How to remove duplicated 2-dimension array in PHP?

My sample array Data:

$arr[] = array(0,1,2,3);
$arr[] = array(4,5,2,1);
$arr[] = array(0,0,0,0);
$arr[] = array(0,1,2,3);

I expected to return

array(array(0,1,2,3), array(4,5,2,1), array(0,0,0,0));

Solution:
$arr = array_map('unserialize', array_unique(array_map('serialize', $arr)));