3v4l.org

run code in 500+ PHP versions simultaneously
<?php $a = [ "foo", "bar", "baz" ]; $b = [ "foo", "baz" ]; $res = array_merge(array_diff($a, $b), array_diff($b, $a)); print_r($res);
Output for 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.32, 8.3.0 - 8.3.33, 8.4.1 - 8.4.24, 8.5.0 - 8.5.9
Array ( [0] => bar )

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112.8 ms | 1550 KiB | 4 Q