Step by Step solution about How to resolve the algorithm Text processing/Max licenses in use step by step in the PHP programming language

This code reads a text file that has a series of lines with the format:

03:47:11:481 IN
03:47:11:775 OUT
03:47:12:600 IN
03:47:12:705 OUT
03:47:25:582 IN
03:47:25:795 OUT

Each line represents an event, where the first column is the timestamp of the event, and the second column is the type of event (either "IN" or "OUT").

The code reads the file line by line and keeps track of the number of people currently in the room. It also keeps track of the maximum number of people that have been in the room at any given time, and the timestamps of the times when the maximum number of people were in the room.

At the end of the code, it prints out the maximum number of people that were in the room at any given time, and the timestamps of the times when the maximum number of people were in the room.

In this example, the output would be:

3
03:47:11:775
03:47:12:705
03:47:25:795

This indicates that the maximum number of people in the room at any given time was 3, and that this occurred at the timestamps 03:47:11:775, 03:47:12:705, and 03:47:25:795.

$handle = fopen ("mlijobs.txt", "rb");
$maxcount = 0;
$count = 0;
$times = array();
while (!feof($handle)) {
    $buffer = fgets($handle);
    $op = trim(substr($buffer,8,3));
    switch ($op){
        case 'IN':
            $count--;
        break;
        case 'OUT':
            $count++;
            preg_match('/([\d|\/|_|:]+)/',$buffer,$time);
            if($count>$maxcount){
                $maxcount = $count;
                $times = Array($time[0]);
            }elseif($count == $maxcount){
                $times[] = $time[0];
            }
        break;
    }   
}
fclose ($handle);

echo $maxcount . '<br>';
for($i=0;$i<count($times);$i++){
    echo $times[$i] . '<br>';
}