3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $c = 'Al(OH)3'; $n = preg_replace('/.*^OOH\)(\d)/i', '$1', $c); echo $n;
based on Fv0d8
Output for 5.6.0 - 5.6.30, hhvm-3.15.4, 7.0.0 - 7.2.6
Al(OH)3