Today's problem B : https://mirror.codeforces.com/contest/652/problem/C
Isn't it the case of stealing/copying a problem? The problem statement was changed only, the problem remains completely the same.
So will it be unrated? Or the copying rule was only for Indian authors?

Clearly, the problems are copied in Global Round 23, but still, why is this contest rated? Previously Codeforces Round #819 was unrated KAN MikeMirzayanov, can you please give us the reason why it's not the case with this round? What's the difference between these two?

Note: If it's a valid reason which distinguishes the two cases then it may be ok. Please don't give reasons like the author himself has submitted the solution to that problem or the description of the test cases was exactly the same in the previous contest.

Is the rating predictor not working correctly or is the rating assigned wrong? For some, it deviates a lot in the negative direction, for some a lot in the positive direction and for some, it approximately matches with the predictor. Can someone please explain why is it occurring? In the previous contests, it had just the error of +- 5, now it's deviating a lot in both directions.
MikeMirzayanov can you please give any update, if it's a mistake from your side or not? These deviations I am seeing for the first time, and even some months back, there was a mistake in assigning the ratings.

I was stress-testing my solution with jiangly's solution, and finally came to the conclusion that his answer is wrong.
His submission : 128262573

Testcase :
1
2 3 5
4 5
1 2 3
6 3
2 2
4 1
9 1
3 2

Correct Answer : 1
His output : 0

MikeMirzayanov please add this testcase.

Can this year's CodeChef Snackdown elimination round be made rated for all? There can be a mirror contest for the participants who could not qualify. This would be great. It's been a long time on CodeChef where there is a combined rank list for all the divisions (external rated for all contests). What are your opinions on this?

Now we have Educational Round on 29th Oct and then another round on 30th Oct. It will be better to put the rounds at a gap 2-3 days so that we do not have to wait for more than 7 days for another contest. Scheduling contests in two consecutive days and then another contest after 7 or 10 days is a bad idea. Rather 3 contests can be distributed such that each contest will have atmax 3-4 days gap.

In the Codeforces Round #727 (Div 2), someone had a rating change of -x and his rank was y. After the plagiarism check, his rank was y-k and had a rating change of -(x+c). Why this occured as rank decreased so either rating change should remain the same or should increase? And that -c is costing that someone person from becoming "Z". Please look into it MikeMirzayanov.
Here, x,y,k and c are all positive and Z is one among them {Pupil, Specialist, Expert, Candidate Master, Master}.

Problem : https://infoarena.ro/problema/xortransform
Why this code passed with 100 points and this code got only 26 points?
The only difference is that in the AC code I did dp[N]={} while in partial AC code I just did dp[N].

Problem : https://dmoj.ca/problem/tle16c6s3
I could not get the editorial's dp states and its recurrence relation. I could follow the editorial till O(n*2^n) approach. Can someone help me?

Hi, can anyone tell me is there any way to solve this problem recursively? In iterative way it's obvious to maintain prefix sums.

Problem : https://www.spoj.com/problems/COOLNUMS/
My dp states : dp[N][partition_1_sum][partition_2_sum][2]
but this is incorrect as we also have to keep track of the order in which numbers are added i guess. can someone tell me what's the approach and how have you implemented it?
My code : https://ideone.com/qw85QZ

Can someone provide me some problems based on MCM type dp states or idea? I have solved this problem only : https://www.spoj.com/problems/MIXTURES/