Looping Through Arrays of Different Length

Question

I have 02 arrays of different length and different elements. Arrays are as follows

$activeRsrvs = [{"reservation_reservationid":"KHAN2016Q221","hotelrooms_hotelroomsid":"1","status":"active"},{"reservation_reservationid":"KHAN2016Q223","hotelrooms_hotelroomsid":"3","status":"active"}]

$allRooms = [{"hotelroomsid":"1","roomno":"01"},{"hotelroomsid":"2","roomno":"02"},{"hotelroomsid":"3","roomno":"50"},{"hotelroomsid":"4","roomno":"15"}]

My code is as follows:

foreach($activeRsrvs as $actvRsrv)
{
    foreach($allRooms as $room)
    {
        if($actvRsrv['hotelrooms_hotelroomsid'] !== $room['hotelroomsid'])
        {
            $output[] = $room;
        } //end if
    } //end inner loop
}//end outer loop

The result which it generates is as follows:

[{"hotelroomsid":"2","roomno":"02"},{"hotelroomsid":"3","roomno":"50"},{"hotelroomsid":"4","roomno":"15"},{"hotelroomsid":"1","roomno":"01"},{"hotelroomsid":"2","roomno":"02"},{"hotelroomsid":"4","roomno":"15"}]

But I want it should return the following result:

[{"hotelroomsid":"2","roomno":"02"},{"hotelroomsid":"4","roomno":"15"}]

The loop erroneously results 6 elements and i want only 02 elements be returned. Kindly help me.

Answer 1

I think the easiest way is to add all rooms to a temp array and then unset them in the loop if they exist in the temp array

Edit: Copy to Paste Solution ;)

$tmp = array();
foreach($allRooms as $room) {
    $tmp[$room['hotelroomsid']] = $room;
}
foreach($activeRsrvs as $actvRsrv)
{
    foreach($allRooms as $room)
    {
        if($actvRsrv['hotelrooms_hotelroomsid'] === $room['hotelroomsid'])
        {
            if(array_key_exists($room['hotelroomsid'], $tmp)) {
                 unset($tmp[$room['hotelroomsid']]);
            }
        } //end if
    } //end inner loop
}//end outer loop
$output = array_values($tmp);