How do I find the shortest overlapping match using regular expressions?

Question

I\'m still relatively new to regex. I\'m trying to find the shortest string of text that matches a particular pattern, but am having trouble if the shortest pattern is a sub

Answer 1

Another regex solution; it finds only the last occurence of .*a.*b.*c:

my_pattern = 'a(?!.*a.*b.*c).*b[^c]*c'

a(?!.*a.*?b.*?c) ensures that there is no 'a.*?b.*?c' after first 'A' strings like A|A|B|C or A|B|A|B|C or A|B|C|A|B|C in results are eliminated

b[^c]*c ensures that after 'B' there is only one 'C' strings like A|B|C|B|C or A|B|C|C in results are eliminated

So you have the smallest matching 'a.*?b.*?c'