3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = array(-1 => 'none'); $b = array(15 => '15 sec', 30 => '30 sec', 60 => '1 min'); var_dump(array_merge($a, $b)); var_dump($a + $b);
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, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
array(4) { [0]=> string(4) "none" [1]=> string(6) "15 sec" [2]=> string(6) "30 sec" [3]=> string(5) "1 min" } array(4) { [-1]=> string(4) "none" [15]=> string(6) "15 sec" [30]=> string(6) "30 sec" [60]=> string(5) "1 min" }

preferences:
243.91 ms | 406 KiB | 328 Q