3v4l.org

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<?php $old = 'james,john,mark,luke,'; $users = 'james,john,mark,luke,mary,david'; $expr = rtrim(preg_replace('/\,/', '|', $old), '|'); $newstr = preg_replace("/$expr/i", '', $users); echo trim($newstr, ',');

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27.93 ms | 402 KiB | 5 Q