3v4l.org

run code in 500+ PHP versions simultaneously
<?php $re = '/(\{([GUW])})\1*|./'; $str = '{1}{G}{G}{U}{U}{W}'; $result = preg_replace($re, '$2', $str); echo $result;
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.21, 8.5.0 - 8.5.7
GUW
preferences:
89.46 ms | 1249 KiB | 4 Q