Php正则表达式preg_match重复字符

Question

I have a string in php like this.

$string = "123451" 

which contains non-consecutive repeated characters of 1. How do i match the repeated characters using preg_match.

I browsed around and found preg_match('/(.)\1\1/', $string)) but it only works for repeated consecutive characters.

Answer 1

What about something like

(\d+).*\1

If you get any match there is a repeated number.