$re = '/(?<=\.\d{2}).*/m';
$str = '/* Note: input consist digits[0-9] and one dot\'.\' only, before the match starts. The input on first line and last line are invalid */
2323.34.34.34.34.
45454.454455445
24334.45654565
65.56434ads5/3d56
24...34..4343';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php