3v4l.org

run code in 300+ PHP versions simultaneously
<?php $def = array( 1 => 'on', 2 => 'on', 3 => 'on'); $fill = array( 2 => 'off' ); $res = array_merge($fill, $def); print_r($res);
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 - 5.6.38, 7.0.0 - 7.0.31, 7.1.0 - 7.1.23, 7.2.0 - 7.2.33, 7.3.12 - 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 ( [0] => off [1] => on [2] => on [3] => on )

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272.58 ms | 406 KiB | 417 Q