3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = [2, 3, 5]; $result = []; foreach ($array as $result[$v * $v][$v] => $v); var_export($result);
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
array ( 4 => array ( 2 => 0, ), 9 => array ( 3 => 1, ), 25 => array ( 5 => 2, ), )
preferences:
173.59 ms | 402 KiB | 123 Q