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<?php $digits = '1234567890'; $alnum = '123test'; //$start = microtime(true); for ($i = 0; $i < 1000; $i++) { preg_match('/^\d+$/D', $digits); preg_match('/^\d+$/D', $alnum); } //printf("%F\n", microtime(true) - $start); /* $start = microtime(true); for ($i = 0; $i < 1000; $i++) { strspn($digits, $digits) === strlen($digits); strspn($alnum, $digits) === strlen($alnum); } //printf("%F\n", microtime(true) - $start); */

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