REGEX - Matching any character which repeats n times

Question

How to match any character which repeats n times?

Example:

for input: abcdbcdcdd
for n=1:   ..........
for n=2:    .........
for n=3:            


        

Answer 1

I would not use regular expressions for this. I would use a scripting language such as python. Try out this python function:

alpha = 'abcdefghijklmnopqrstuvwxyz'
def get_matched_chars(n, s):
    s = s.lower()
    return [char for char in alpha if s.count(char) == n]

The function will return a list of characters, all of which appear in the string s exactly n times. Keep in mind that I only included letters in my alphabet. You can change alpha to represent anything that you want to get matched.