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<?php function isPrime($number) { $max = floor(sqrt($number)); for ($i=1; $i < $max; $i++) { if ($number % $i == 0) return false; } return true; } do { $i = mt_rand(100, 999); } while ( ! isPrime($i) ); var_dump($i);

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31.56 ms | 402 KiB | 5 Q