3v4l.org

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<?php $a = [0, 1, 2, 3, 4, 5, 6]; $b = [4]; print_r(array_udiff($a, $b, function($x, $y) { return $x <=> $y; })); print_r(array_udiff($a, $b, function($x, $y) { return $x != $y; }));

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37.27 ms | 402 KiB | 5 Q