Today, I was notified by Codeforces Bot about potential cheating-like behavior involving a user with the handle nxsang1611, who has the same submission for the problem 2020E — Expected Power.
These are the submissions:
283625609 by me.
283648889 by nxsang1611.
However, no additional information has been provided to clarify who they actually are. Here are the submissions that show significant similarities to my code:
I have some evidence supporting my case:
- Firstly, my code was submitted first. Before the second submission, 283625609, which was accepted, I had submitted 283622331, which is based on the same idea but resulted in a Memory Limit Exceeded error. This demonstrates that the idea originated from me, not from anyone else.
- Additionally, the algorithm of $$$O$$$ $$$(n \times 1024)$$$ per test case is well-known, as it is the formula for calculating the inverse of a prime modulo. The formula for binary exponentiation is widely available here, and the formula for modular inversion can be found here.
According to Codeforces rules, using code published before the contest starts is permitted. Therefore, I believe this coincidence has occurred due to the use of a common source that was available before the competition. I kindly request that the Codeforces administrators MikeMirzayanov, Vladosiya reconsider this case as a false positive detection.
