Regex get last occurrence of a pattern with negative sign

Question

I've been following Freecodecamp's tutorial on Regex to be able to get the last occurrence of the pattern I intend to get. I intend to get the number (with / without a negative sign), the number, and any character that comes after that.

Goal:

    aa-11aa -> gets the -11aa
    11aa -> gets the 11aa
    aa11aa11aa -> gets the 2nd 11aa
    aa-11aa-11aa -> gets the 2nd -11aa
    aa-11a(a) -> gets the -11a(a)

However, I've only gotten this pattern to work to only get a single digit and the post fix of whatever comes after the number. (?:.*)(-*\d+)(.*)$. These are the results from my pattern:

Issue:

    aa-11aa -> gets the 1aa
    11aa -> gets the 1aa
    aa11aa11aa -> get the 2nd 1aa
    aa-11aa-11aa -> get the 2nd 1aa
    aa-11a(a) -> gets the 1a(a)

Any help on how I can get my desired result?

How about (?:.*?)(-*\d+)(.*)$. Making the first group nongreedy — xdhmoore, Jul 18 '20 at 05:08

smmehrab · Answer 1 · 2020-07-18T05:53:40.657

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Try this:

-?\d+[^\d]+$

It was including the second occurrence of the digits too, as . means any character.

Note that, \w matches any word character (equal to [a-zA-Z0-9_])

edited Jul 18 '20 at 05:53

answered Jul 18 '20 at 03:58

smmehrab

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It's a good attempt; however, it isn't able to get **any** character after the number. I wasn't able to add an example where a string can be `aa-11a(a)`. – CraftedGaming Jul 18 '20 at 04:59
You wanted **any character** after the number? Modified the answer. – smmehrab Jul 18 '20 at 05:13
it's currently matching all occurrences. I only intend to get the last one – CraftedGaming Jul 18 '20 at 05:29
Updated. This should do. – smmehrab Jul 18 '20 at 05:48
yup. that works too. thanks! – CraftedGaming Jul 18 '20 at 05:51

score 1 · Accepted Answer · answered Jul 18 '20 at 05:15

1

The following should work

.*?(-?\d+[^\d]*)$

First non-greedily match any preceding characters, then in your group conditionally match the minus sign followed by some numbers followed by zero or more characters that are not a number

answered Jul 18 '20 at 05:15

Iain Shelvington

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Regex get last occurrence of a pattern with negative sign

2 Answers2