3v4l.org

run code in 300+ PHP versions simultaneously
<?php $values = [ 'ffffffff' => 'a', 'ffflohff' => 'b', 'lohlohff' => 'c', ]; $filteredValues = array_intersect_key($values, array_flip(preg_grep('/loh/', array_keys($values)))); var_dump($filteredValues);
Output for 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
array(2) { ["ffflohff"]=> string(1) "b" ["lohlohff"]=> string(1) "c" }
preferences:
92.72 ms | 406 KiB | 5 Q