The day before yesterday, I participated a Div.2, and managed to get the last place. I left my computer with satisfactory, and 2 players got lower rank than me but I think that shouldn't make any difference.

But I gained +6 rating.

https://mirror.codeforces.com/bestRatingChanges/17288893

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Wow! Coder BouncyHunter competed in Codeforces Round 1021 (Div. 2) and gained +6 rating points taking place 5855
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I was wondering why and how, it still had a positive delta, and how to prevent it. Should I continue in today's Edu or not?

By the way, displayed on the rating changes page is "delta = 0 100 → 100". Is that a bug of Codeforces?