$newarr = array();
$oldkey = NULL;
while ($key = array_shift($dis)) {
if ($oldkey !== NULL)
unset($newarr[$oldkey][$key]);
$newarr[$oldkey = $key] = $arr = $arr[$key];
}
$newarr = array();
$oldkey = NULL;
while ($key = array_shift($dis)) {
if ($oldkey !== NULL)
unset($newarr[$oldkey][$key]);
$newarr[$oldkey = $key] = $arr = $arr[$key];
}