$sql = "SELECT * FROM `menu` WHERE `loc`=0";
$result=$conn->query($sql);
while ($row = $result->fetch_assoc()){
$sql_loc = "SELECT * FROM `menu` WHERE `loc`=".$row['id'];
$result_loc=$conn->query($sql_loc);
if ($result_loc->num_rows > 0){
?>
while ($row_loc = $result_loc->fetch_assoc()){
$sql_loc3 = "SELECT * FROM `menu` WHERE `loc`=".$row_loc['id'];
$result_loc3=$conn->query($sql_loc3);
if ($result_loc3->num_rows > 0){
?>