3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = ['a' => 1, 'b' => 2, 0, 'f' => 4, '-f' => 5]; ksort($array); /** Array ( [-f] => 5 [0] => 0 [a] => 1 [b] => 2 [f] => 4 ) */ ?>
Output for 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3

preferences:
58.77 ms | 834 KiB | 4 Q