Recently, when I was wandering around Codeforces Round 970 (Div. 3) submissions, i have noticed some aditya8806701281's submissions seem to be suspicious. This user has never ranked higher than 5000 in any contest before but in this contest he rose to the top 500.

Have a look:

Problem 2008H - Sakurako's Test: 279214387 As you can see, too many long-name variables and there is an unnecessary function (right after the defines) that he calls for nothing in the solve function.

Problem 2008G - Sakurako's Task: 279207870 The same thing from his solution from problem H.

Problem 2008F - Sakurako's Box: 279133796 Variable names seem too long.

Problem 2008D - Sakurako's Hobby: 279107529 2 extra functions for nothing, and he called them in the solve() function.

Problem 2008C - Longest Good Array: 279099481 Do you think the function randomOrder1() has any purpose?

Problem 2008B - Square or Not: 279087122 I don't think he even cheated on B div3, but have a look. 2 randomFunction with no purpose.

Problem 2008A - Sakurako's Exam: 279078136 If he cheated on A div3, idk what is he doing here. But I saw the "randomFunction" and yeah, who even do that?

Another 2 submissions I considered as worth seeing:

279179329 279116768

When I gave it to AI detector for code, here is the result:

First sub: (comments doesn't count, they have existed in the user's codes for a long time) 75% and 92% (Comment if you want the checker)

Second sub: (I pasted it directly for the AI to check) 75% and 88%

These 2 submissions was given to me by 2 codeforcers, and I don't find them myself. I don't want to say if they are cheaters, but this one is worth considering. Also, I did not say these codes are AI-generated, I just took these numbers from AI detector.

Hello codeforces!

I would like to search for help about a problem:

Given $$$n$$$ points $$$x_i, y_i(|x_i|,|y_i|<=10^4)$$$ and $$$q$$$ queries. The $$$j^th$$$ query consists of 3 integers $$$C_j x, C_j y, z_i$$$ $$$(|C_j x|, |C_j y|<=100,1<=z_i<=180)$$$: taking the center as $$$(C_jx, C_jy)$$$, rotate all n given points $$$z_i^o$$$ counterclockwise. Print the position of n points after q queries. Constraints: $$$1<=n,q<=10^5$$$

(This is not my problem, and i just want to ask for idea because there is no online judge for this)

Sample test:

Input:

3 1

1 1 90

2 1 180

1 2 90

3 3

Output:

4.0000000000 6.0000000000

I want to ask for ideas that works with large $$$n,q$$$(Up to $$$10^5$$$) because for $$$O(nq)$$$ just brute-force for all points.

Thanks!

Hello codeforces!

I have a question about prime numbers. Is there a way to determine whether an integer is a prime or not in O(log(n)) time complexity?

Thanks!

I want to ask about this problem: 622F - The Sum of the k-th Powers. I solved it using lagrange interpolation 263080914 but can anyone help me implement the solution with Faulhaber's formula? Thanks very much.