Regex look back format condition

Question

I need help to make a regex that can match specific format.

Input:

\"fr. 2 699:- 2 fr. 599:- 3 fr. 899:- 4 fr. 3 899:- 5 fr. 1 49

Answer 1

How about this:

Online Demo

/(?<=fr\.\s)(\d{3})/g

Answer 2

It seems you want to match the numbers that follow fr.

The following regex should work:

fr\. ([1-9]\d{2})

Tested at: http://rubular.com/r/ct5WD9TlTg