Remove consecutive elements given a starting key and an ending key

Question

I have an input array with keys representing 24-hour "military" time and values representing 12-hour "am/pm" time. I want to remove consecutive elements from my array determined by two variables that contain "military" time values.

Here are my input variables:

$starttime = '5';
$endtime = '17';
$timings = array(
     '0' => '12AM',
     '1' => '1AM',
     '2' => '2AM',
     '3' => '3AM',
     '4' => '4AM',
     '5' => '5AM',
     '6' => '6AM',
     '7' => '7AM',
     '8' => '8AM',
     '9' => '9AM',
     '10' => '10AM',
     '11' => '11AM',
     '12' => '12PM',
     '13' => '1PM',
     '14' => '2PM',
     '15' => '3PM',
     '16' => '4PM',
     '17' => '5PM',
     '18' => '6PM',
     '19' => '7PM',
     '20' => '8PM',
     '21' => '9PM',
     '22' => '10PM',
     '23' => '11PM',
);

foreach ($timings as $t) {
    
}

I would like to iterate the timings in a foreach loop, but before that, I would like to remove the timings between start time and end time.

Here my $starttime key is 5 and my $endtime key is 17.

So I would like to remove 5,6,7,8,9,10,11,12,13,14,15,16,17 from the array and keep the remaining elements.

Can some tell me how to pop those elements out?

Answer 1

Slice and Merge

Just use array_slice and array_merge like this:

$starttime = '5';
$endtime = '17';

$timings = array_merge(
              array_slice($timings, 0, intval($starttime)),
              array_slice($timings, intval($endtime) + 1)
           );

---

Splice

Another way which is simpler and a (insignificantly) more efficient is using array_splice. Notice that it returns the extracted array, and changes the original array, so don't place the result inside $timings.

$starttime = '5';
$endtime = '17';

array_splice($timings,
             intval($starttime),
             (intval($endtime) - intval($starttime))
            );

Answer 2

I feel that it is necessary to spell out that some techniques will destroy the original keys and other will preserve the original keys.

Codes: (Demo)

Loses Keys

function spliceKeys($timings, $starttime, $endtime) {
    array_splice($timings, $starttime, $endtime - $starttime);
    return $timings;
    
}

function sliceKeys($timings, $starttime, $endtime) {
    return array_merge(
              array_slice($timings, 0, $starttime),
              array_slice($timings, $endtime + 1)
           );
}

Keeps Keys

function diffKeys($timings, $starttime, $endtime) {
    return array_diff_key($timings, array_flip(range($starttime, $endtime)));
}

function skipKeys($timings, $starttime, $endtime) {
    $result = [];
    foreach ($timings as $military => $timing) {
        if ($military >= $starttime && $military <= $endtime) {
            continue;
        }
        $result[$military] = $timing;
    }
    return $result;
}

function unsetKeys($timings, $starttime, $endtime) {
    $result = [];
    foreach ($timings as $military => $timing) {
        if ($military >= $starttime && $military <= $endtime) {
            unset($timings[$military]);
        }
    }
    return $timings;
}