3v4l.org

run code in 300+ PHP versions simultaneously
<?php $str='0x0fc929cc'; $regex='/[0-9a-f]{3,5}(c+)$/i'; preg_match($regex,$str); if (preg_match($regex,$str,$matches)){ echo $matches[1];} else { echo 'b'; } ?>

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46.45 ms | 402 KiB | 5 Q