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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 - 8.2.34, 8.3.0 - 8.3.35, 8.4.1 - 8.4.26, 8.5.0 - 8.5.11
120

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27.49 ms | 1151 KiB | 7 Q