How to capture multiple repeated groups?

Question

I need to capture multiple groups of the same pattern. Suppose, I have a following string:

HELLO,THERE,WORLD

And I\'ve written a following

Answer 1

I know that my answer came late but it happens to me today and I solved it with the following approach:

^(([A-Z]+),)+([A-Z]+)$

So the first group (([A-Z]+),)+ will match all the repeated patterns except the final one ([A-Z]+) that will match the final one. and this will be dynamic no matter how many repeated groups in the string.