How to write a regular expression to capture several OKVED?

Question

Regular Expressions

I tried to write myself: But it's not right and not up to the end. You need to capture the following types of oqueds ( 1 === \d{1} ):^[\d]{2}(?:[\.\,]{0,2}[\d]{0,2})$

• eleven
  
• 11.1 (or 11.1)
  
• 11.11 (or 11.11)
  
• 11.11.1 (or 11.11.1)
  
• 11.11.11 (or 11.11.11)
  
• 11 11.11 11.11.11
  
• 11 11.11 11.11.11
  

Invalid:

• 11. (or 11,)
  
• 11.1. (or 11.1,)
  
• 11.11. (or 11.11,)
  
• 11.11.1. (or 11,11,1,)
  
• 11.11.11. (or 11,11,11,)
  

Answer 1

^\d\d(?:[ .,]\d\d?)*$
https://regex101.com/r/HNNPVh/1
If invalid:

• 11.11.11
  
• 11.11.11
  
• 11.1.11
  
• 11.1.1
  

^\d\d(?:([.,])\d(?:\d(?:\1\d\d?|)|)|)(?: \d\d(?:([.,])\d(?:\d(?:\2\d\d?|)|)|))*$

https://regex101.com/r/HNNPVh/2

Answer 2

d(?=r) matches d only if followed by r but r will not match expression -> test
(?<=r)d matches d only if preceded by r but r will not match match expression -> test
plus
[^d]+ all up to d