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<?php $subject = "101010101"; $pattern = "/[01]{1,4}/"; preg_match_all($pattern, $subject, $match); echo '<pre>', print_r($match[0]);
Output for 7.1.25 - 7.1.30, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
<pre>Array ( [0] => 1010 [1] => 1010 [2] => 1 ) 1
preferences:
111.97 ms | 403 KiB | 172 Q