I haven't used regex much and I'm trying to learn a bit of it now.

I want to look for three possible patterns in a string at least two times. the patterns I'm looking for are at the start of a string, it can be 2; , somewhere in the middle of a string, it can be ;2; and at the end of a string, it can be ;2

The what I'm doing now is (^2;.*|.*;2;.*|.*;2$){2}.

This seems to work for the most part, but I cant figure out why a2;2;2 isn't matching. the ;2;, and ;2 should match I believe.

CodePudding user response：

Quantifiers won't count overlapping occurrences of the pattern. Since the ; characters are included in the match, you won't find matches where the ending ; of one match is the starting ; of the other.

You can solve this by using lookarounds to take the ; out of the match.

(?<=^|;)2(?=;).*(?<=;)2(?=;|$)

DEMO

CodePudding user response：

You could try (with look-arounds around the 2):

(?:^2(?=;)|(?<=;)2(?=;)).*(?<=;)2(?=;|$)

Regex demo.