3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = array('k' => array(1,2), 'j' => array(3,4)); var_dump($a);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array(2) { ["k"]=> array(2) { [0]=> int(1) [1]=> int(2) } ["j"]=> array(2) { [0]=> int(3) [1]=> int(4) } }

preferences:
313.13 ms | 406 KiB | 456 Q