05. Add/Remove Elements

<?php
if(isset($_GET['delimiter']) && isset($_GET['commands'])) {
    $delimiter = $_GET['delimiter'];
    $commands = $_GET['commands'];
    $commands = explode("\n",$commands);
    $commands = array_map('trim',$commands);
    $result = [];
    for ($i = 0; $i < count($commands); $i++) {
        $command = explode($delimiter,$commands[$i]);
        $commandKey = $command[0];
        $commandValue = $command[1];

        if($commandKey=="add") {
            array_push($result,$commandValue);
        }
        else {
            array_slice($result,$commandValue,1);
        }
    }
    for ($i = 0; $i < count($result); $i++) {
        echo $result[$i] . "<br>";
    }
 }