I just saw in a recent Leetcode contest that there were thousands of submissions during a contest with almost the same code/solution. I can't imagine that's only happening on Leetcode, right? If this is a problem on Codeforces, I'm curious how it's handled? Thanks
I don't think it's possible to submit the same code from different accounts without being detected by codeforces anti-cheat. I assume (or at least hope) Leetccode has a similar system and simply waits until the end of the contest to find cheaters, and that's why they are not blocked yet, but I don't know. In any case it's best when annoying cheaters are handled automatically, so there's probably a system for that in every major website.
No, leetcode doesn't detect people who submit the same code on 2 different accounts. Only jinlibao's plagiarism checker can detect that and iirc most of them are still rated with no penalty imposed