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<?php $factorial = function (int $n) use (&$factorial) { if ($n === 1) { return 1; } return $factorial($n - 1) * $n; }; print $factorial(5);
Output for 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.21, 8.5.0 - 8.5.6
120

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44.44 ms | 844 KiB | 4 Q