I spent some time today working on a system to identify similar problems along the lines of https://codeforces.net/blog/entry/113064. For testing, it would be nice to have a list of duplicate (or close to duplicate, "one simple transformation" away, etc.) problems on Codeforces. The only pair I am currently aware of is (1793F - Ребрендинг, 765F - Сувениры), so any others would help. Thanks!

EDIT: Just to be clear, I'm not interested only in strict duplicates, but also problems that share some important subtask, observation, or pairs in which one problem is a generalization of the other. And not asking for anyone to put any work into this, just thought some people might have pairs that come immediately to mind :)