A friend of mine told me about a suspected cheater, [user:batats,2026-05-23], so I decided to check his submissions myself. Here are a few reasons why I suspect that [user:batats,2026-05-23] may have cheated in some recent contests.↵
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## 1. Rapid Rating Increase↵
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He registered on Codeforces 5 years ago and stayed at newbie level for a very long time, with his rating never exceeding 1200. However, during the last 2 months, his rating suddenly skyrocketed.↵
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He went from 1107 rating after Educational Codeforces Round 188 to 2107 rating after Codeforces Round 1099 (where he achieved rank 2) in only 6 contests.↵
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Of course, rapid improvement is not impossible. Some people improve very quickly. However, after looking at his submission history, the jump feels suspicious. Earlier, he was solving around 3 out of 7 problems in Div. 2 contests, but only 2 months later, he suddenly solved 6 out of 6 problems in a much stronger performance.↵
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Maybe it is legitimate, but the improvement speed is unusual enough to raise questions.↵
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## 2. Sudden Changes in Coding Style↵
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Another thing I noticed was the inconsistency in his coding style.↵
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In the first 4 contests among these recent rounds, his code looked very cluttered:↵
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* compact formatting,↵
* very few spaces,↵
* dense implementation style.↵
↵
Then, in the 5th contest, he suddenly switched to a completely different style. While changing templates is perfectly normal, the way he wrote code inside `main()` and other functions also changed noticeably:↵
↵
* cleaner formatting,↵
* much more spacing,↵
* overall more readable structure.↵
↵
But in the 6th contest, although he still used the new template, he immediately went back to his old cluttered coding habit.↵
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That sudden one-contest-only change feels strange. Usually, coding style is one of the most consistent habits for competitive programmers.↵
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Again, this is **only suspicion, not proof**. There may be completely legitimate explanations for all of this. If [user:batats,2026-05-23] wants to clarify anything, he (or she) is welcome to respond in the comments.↵
↵
## 1. Rapid Rating Increase↵
↵
He registered on Codeforces 5 years ago and stayed at newbie level for a very long time, with his rating never exceeding 1200. However, during the last 2 months, his rating suddenly skyrocketed.↵
↵
He went from 1107 rating after Educational Codeforces Round 188 to 2107 rating after Codeforces Round 1099 (where he achieved rank 2) in only 6 contests.↵
↵
Of course, rapid improvement is not impossible. Some people improve very quickly. However, after looking at his submission history, the jump feels suspicious. Earlier, he was solving around 3 out of 7 problems in Div. 2 contests, but only 2 months later, he suddenly solved 6 out of 6 problems in a much stronger performance.↵
↵
Maybe it is legitimate, but the improvement speed is unusual enough to raise questions.↵
↵
## 2. Sudden Changes in Coding Style↵
↵
Another thing I noticed was the inconsistency in his coding style.↵
↵
In the first 4 contests among these recent rounds, his code looked very cluttered:↵
↵
* compact formatting,↵
* very few spaces,↵
* dense implementation style.↵
↵
Then, in the 5th contest, he suddenly switched to a completely different style. While changing templates is perfectly normal, the way he wrote code inside `main()` and other functions also changed noticeably:↵
↵
* cleaner formatting,↵
* much more spacing,↵
* overall more readable structure.↵
↵
But in the 6th contest, although he still used the new template, he immediately went back to his old cluttered coding habit.↵
↵
That sudden one-contest-only change feels strange. Usually, coding style is one of the most consistent habits for competitive programmers.↵
↵
Again, this is **only suspicion, not proof**. There may be completely legitimate explanations for all of this. If [user:batats,2026-05-23] wants to clarify anything, he (or she) is welcome to respond in the comments.↵
