The goal of this issue is to add a new concept to the Java track that introduces sets. The corresponding concept exercise can be probably be based on one the following exercises from other tracks:

• Gotta Snatch 'Em All from the Elm track
• Ozan's Playlist from the Javascript track

Instructions on how to contribute to the Java track and how to implement concept exercises can be found in the contributing guide.

As always, leave a comment here if you want to work on this exercise, and we'll assign it to you. In case you have any further questions, feel free to ask here.