3v4l.org

run code in 500+ PHP versions simultaneously
<?php $ht = array(1 => 1, 2 => 2, 3 => 3, 4 => 4); $range = range(1,10); $diff = array_diff($range, $ht); Echo str_repeat("x", count($ht)) . Implode("", $diff);
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
xxxx5678910

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42.64 ms | 1402 KiB | 4 Q