Extracting differences between two lists

Priviet !

I am new to Zennoposter and I'm trying to understand something. It sounds pretty simple, but I can't figure out how achieve what I want. I already searched for a solution on these forums, with no success (I saw some good info about how to extract the common items in two lists, however here I only need to extract the differences between two lists).

I have two lists:

1. Followers (say for example 150 followers) (like followerA,followerB,followerC,followerD...)
2. Followed (say 200 followed) (like followerA,followerB,followerC;followerD,followerE...)

My goal here is to:

1. Compare Followers / Followed list then
2. Keep only entries from the Followed list which don't also appear in the Followed (basically get a list of accounts I followed but don't follow me back, followerE in my example)

So I tried to do the following:

1. Merge the Followers list and add it to a variable FollowersMerged
2. Get random line from the Followed list (and delete after take) an assign it to a variable named RegexFollowed
3. Do text processing : apply a Regex (using the RegexFollowed variable) to the FollowersMerged variable and add the result to a variable named Found
4. Use IF with "(-Variable.Found-)"!="". If the outcome is negative, restart step 2

But I'm not getting what I want. Looks I'm missing something here (and very simple I guess), but I need to get my brain used to this kind of gymnastics.

I'd be very glad if anyone could help me here. Thank you!

Thank you for answering ! I m gonna try that

Just a follow up here, I completed this simple operation and I should have looked better to find that delete line option.

Thank you again.