3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a1 = array(1=>1, 2=>2, 3=>3, 4=>4, 5=>5, 6=>6, 7=>7); $a2 = array(2=>2, 4=>4, 6=>6, 8=>8); $a3 = array_diff($a2, $a1); var_dump($a3);

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34.06 ms | 402 KiB | 5 Q