3v4l.org

run code in 300+ PHP versions simultaneously
<?php $re = '~(?:<p>(?=[^<>]*</p>)|\G(?!^))[^\d<>]*\d+\K\h~'; $str = '<p>My 90 days 123 work.</p>'; echo preg_replace($re, "&nbsp", $str);

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24.29 ms | 404 KiB | 5 Q