Regex for Comma Separated Number or Just Number

Question

This is something of a follow up from a previous question. The requirements have changed, and I\'m looking for some help with coming up with regex for either a comma separated n

Answer 1

Try this:

^\d{1,3}(?:(?:,\d{3})+|\d*)$

This will match any sequence that begins with one to three digits, followed by either

• one or more segments of a comma followed by three digits, or
• zero or more digits.