Find repeating characters in a string using regex

Question

I'm trying to find a regex which finds 3 repeating characters appearing contiguously in a string. The character set could be alphabet, digit or any special character.

I wanted the first try for alphabet and digits and then extend the expression to include special characters. The ones I tried are. Both of these fail for the string "c2sssFg1". What am I doing wrong here?

(\\w*)\\2{3,}(\\w*)

(\\w*?)(\\w)\\2{3,}(\\w*)

I looked at some of the examples on SO and on web but I didn't find the right solution that passes the random strings I test. Can someone help me with this?

Thanks.

What about `(\w)\1{2}`? Obviously escaping the backslashes with a second one. — ctwheels, Mar 06 '18 at 19:38

IWHKYB · Accepted Answer · 2018-03-06T19:50:34.780

6

(.)\1{2}

(.) matches any char

\1 matches that exactly char

{2} is to grant its 2 more of that

edited Mar 06 '18 at 19:50

answered Mar 06 '18 at 19:41

IWHKYB

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Looks like this worked for me. Thanks for your help. – uncommon_breed Mar 06 '18 at 22:23

score 1 · Answer 2 · answered Mar 06 '18 at 19:48

1

Try (.)\1\1. It works for general case.

answered Mar 06 '18 at 19:48

NiVeR

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Find repeating characters in a string using regex

2 Answers2