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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 - 8.2.32, 8.3.0 - 8.3.33, 8.4.1 - 8.4.24, 8.5.0 - 8.5.9
120

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62.42 ms | 879 KiB | 4 Q