3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = [1, 2, 3]; unset($a[2]); $a[] = 4; var_dump($a);
Output for 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
array(3) { [0]=> int(1) [1]=> int(2) [3]=> int(4) }

preferences:
68.01 ms | 406 KiB | 5 Q