At the moment I agree with point 6. The rejudging process for the challenge problem MUST be more transparent. The rejudging is currently not over and it’s not even sure that submissions are still being rejudged. The contest is not over until the rejudging of the submissions for the problem SEAVEC is over, so I prefer not to write any (more) feedback until the contest is really over.
@mugurelionut It seems that CodeChef announced on Facebook that the rejudging is done. I don’t believe it.
@admin Please look into the scores for the challenge problem as soon as possible. There is a lot of confusion whether all the submissions have been rejudged or not and the solutions are showing different scores in the practice section. Please clarify this immediately.
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@kevinsogo: Thanks for the link. I wasn’t aware of that. Yes, the rejudging is NOT over. But I am very disappointed to see that not even the admins have a method of knowing if the rejudging is over or not. I think now that this post-contest rejudging was a very poor decision, because it seems that the existing infrastructure is not sufficient for a smooth post-contest rejudging process.
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@admin: As others have mentioned, please check if the rejudge had been run against all submissions or only the ones with TLE & WA? While the rejudge was going on, I noticed that only my submissions which were TLE were rejudged (inferred from the animated icon during submission judging) while the AC ones were not.
@deepai_dutta Just curious, whats with p^(q-1)? Is it that numbers of this form have prime number of factors? Please correct me if I am mistaken.
@beethoven yes. number of the form p^(q-1) have prime no. of factors provided both p and q are prime
There is an issue in the rejudging of challenge problem of November Long 2013. We are looking into this. We will let you know once we figure out the issue and do a rejudge again. Please bear with us.
We regret the inconvenience caused.
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What was your method for MCHAIRS?
I just knew the reduction method to fast exponentiation when I first set this problem, but, it was also possible to precompute powers of two and then taking O(1) time to answer each query without explicitly using fast exponentiation, such as this: CodeChef: Practical coding for everyone
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Yes we are aware of this and we truly regret the issues. We will fix them going ahead and will try to be more responsive in the status of the rejudging.
I agree always you’ll find questions based on sequences…!!!
As far as I understand solution to ‘Chef game’ (Hackenbush solution) does not depend on the uniqueness of numbers in pile. In fact adding repeating numbers to the piles will not affect the result at all. If you think about it then you will understand that repeating numbers give no advantage to anybody because they all repeated numbers will be removed at the same time altogether.
@snowbear: I think @kcahdog refers to the fact that they were unique in the test cases, although the problem statement allowed for duplicates. And many contestants forgot to remove the duplicates and still got AC. But I also agree that this is a minor issue. Removing the duplicates is a trivial step. Many of the accepted submissions which did not remove the duplicates could have been fixed immediately during the contest.
Well, I solved them rather differently (I used heavy path decomposition for GERALD2, but I used something else entirely for MONOPLOY). But it’s true that they were very data structures-oriented. In fact, all the three difficult problems (GERALD2, MONOPLOY and QPOINT) were data structures-oriented (for instance, I used segment trees in various forms for each of these 3 problems). Compared to this, last month’s difficult problems were very different (one based on number theory and the other one based on dynamic programming over the block-cut vertex tree of a graph).
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I think if they do it in the editorials they’ll become too long… If you don’t understand something you can ask in the comments or google it 
@junior94 i know but what i understand by editorials is that they must present all the concepts related to problem very precisely and efficiently.we must also keep in mind as these publish only once in a month so they can be detailed.again it is my way of thinking.
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@snowbear Please refer to this : CHEFGM - Editorial - editorial - CodeChef Discuss. It is a minor issue but i just felt problem statements should be prepared with more care in the future to avoid confusion like this later.
@admin
For challenge problem
Why only TLE submissions are taken into account ?
Even though these solutions gave AC at the time of contest but now these solutions are timing out ?
What is wrong with the rejudging ?
There some serious issues in Ranking also because of rejudging.
This is really not acceptable 
The cases of the AC solutions getting TLE will be looked into. There was some issue in the re-judging the solutions the first time around. We have rejudged them now. However, due to so many solutions getting queued for a rejudge, the load on the online judge increases with resource contention coming into picture. This makes the judge slower and some solutions may get TLE’d. Please do not worry about them as we will try and make sure that all AC solutions during the contest get AC even after rejudge.
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