3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php $string = 423.13; echo preg_replace_callback("/^(\d)([^\.]+)/", function($m){ return $m[1] . str_repeat(0, strlen($m[2])); }, $string);
Output for 5.5.0 - 7.3.0rc6
400.13