[REGEX] How to make this regex expression more specific?

[sS]?(\d{1,2})

I would like to get a \d{2} if [sS] was found, else accept both
\d{1} and \d{2}

Thank you for your help.


Regards,
Zananok

You could use alternation:

([sS]\d{2})|([^sS]\d{1,2})

I tried it in Perl, it seems to be doing what you want.

And with just a little change should work in a posix or gnu ERE:

Code:

([sS][0-9]{2})|([^sS][0-9]{1,2})

So, Spacebar, thank you for the comment, it seems to be saying that \d is not posix or gnu ERE, so that you replace it with a character class [0-9], I didn't know this was neither posix nor GNU.

But it is a quite common feature of regex nowodays in many languages. And the OP used that syntax, so I would tend to think that this is available to her or him.

Thank you for the information, anyway.