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);

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52.75 ms | 1404 KiB | 5 Q