Блог пользователя Tensei8869

Автор Tensei8869, 3 года назад, По-английски

We are back again with another edition of IIIT Lucknow’s much awaited and exhilarating annual team coding event CODUO. Similar to the last edition, the event will be held on Codechef on the 28th of April from 9PM IST.
But unlike the last edition, this time CODUO will be a single round event spanning 3 hours (Individual participation or Team of 2 members), and the problem set will contain 8-9 problems of varying difficulty.

Contest Link: https://www.codechef.com/CDDU2022

This contest is a part of our annual technical fest — Equinox`22, IIIT Lucknow.

Last year’s CODUO contest was accompanied by a prodigious participation of over 900 teams and this edition will hopefully witness even more participation than before.
Here are the major participants and the prelims winners of last time:
- Geothermal
- CoderAnshu
- rivalq
- kal013

PRIZES:
The Winners of CODUO will be awarded total prizes worth INR 15,000

We hope the problem-set will contain interesting problems for participants of all levels and that you’ll enjoy the contest just as much as we did preparing it!!

Update: The round has been shifted to 28th of April instead of 25th, sorry for any inconvenience caused.
Update 2: The team registration link is working again, you can register now if you weren't able to before

All the Best!

  • Проголосовать: нравится
  • +35
  • Проголосовать: не нравится

»
3 года назад, # |
  Проголосовать: нравится +16 Проголосовать: не нравится

Didn't Codechef stop giving Laddus??

  • »
    »
    3 года назад, # ^ |
      Проголосовать: нравится 0 Проголосовать: не нравится

    Yes, that was a misunderstanding on our part since the removal of laddus was a very recent change, I have updated the blog accordingly

»
3 года назад, # |
Rev. 2   Проголосовать: нравится +104 Проголосовать: не нравится

Given that I was tagged in the announcement, I feel an obligation to note that I do not endorse this contest. I was not awarded a prize that I won last year; here's a screenshot of my correspondence with the organizers:

Note that there was no response to my email; I've scoured all my inboxes and my CF DMs, and I can't find any other correspondence with the organizers (if there's some way y'all communicated with me that I missed, please let me know!). The issue may be that that the organizers are unable to transfer prizes to banks outside of India, but if that's the case, (a), they should have responded to me and said so, and (b), they should have specified in the contest announcement that only Indian competitors, or perhaps competitors with Indian bank accounts, are eligible to receive prizes (and they should update the announcement this year to reflect this). I have absolutely no problem with contests in India restricting prizes to Indian competitors, either because of issues with payment logistics or even simply because their primary goal is to support competitive programming/competitive programmers in India. However, if your prizes are region-locked, you should say so in advance.

Unfortunately, prizes not being awarded has been a fairly common experience in these sorts of contests (I'd estimate I've received approximately 1/3-1/2 of the prizes I won across a number of similar contests), to the degree that I don't post comments every time it happens. In this case, though, I'm frustrated that the organizers of this contest promised a prize, failed to deliver it or even to respond to my email, and then used my participation to advertise their event, so I feel the need to call out this behavior. In short, if you are a high-level competitor participating from outside of India, you should not assume that you will receive the promised prizes.

I should also note that there were a number of logistical issues with the finals last year; e.g., I recall being unable to log into the CMS for the finals before adding a fake second member to my team, and I think there was an issue with the data or checker for one of the problems, but I can't remember the details and might be confusing this with another contest. Again, these issues are reasonably common and I don't call them out every time they happen, but the combination of the preparation errors and the issues with prize distribution left a very sour taste in my mouth.

  • »
    »
    3 года назад, # ^ |
      Проголосовать: нравится -9 Проголосовать: не нравится

    We are sorry for this unfortunate incident. It was a pleasure having you as a participant in the previous edition. We were ecstatic with everyone's positive review on the Prelims last year, we do regret the issues caused by Hackerearth and wish the finals could have been handled better.

    As for your case, we are extremely sorry for the way that communications were handled from our end, however we received a mail from you (which you've attached above) saying that international transfers were a hassle from your end, and so it would be okay to forfeit the prize incase we could not use alternate methods, similarly our institute has a policy regarding prize distribution and it would be really tough to go around that. It was only because of that and because you said it would be okay to forfeit the prize that we decided to forego giving you the prize. Once again we really regret the way communication was handled but things were messy for us as well at the times because of COVID.

    But this time we have made sure that the International participants also receive their due prize and we will ensure that things are handled better as we are working offline. Same as the last edition, we have worked really hard on preparing this contest and we hope you won't let this mistake affect your perception of us badly.

    • »
      »
      »
      3 года назад, # ^ |
        Проголосовать: нравится +32 Проголосовать: не нравится

      Thanks for your response! I understand that dealing with international transfers can be difficult, but I would have expected to receive a response to my email, and I would have hoped that if you were unable to distribute prizes internationally, you would have specified that restriction in the contest announcement. Hopefully these issues can be avoided in the future; best of luck running the contest this year.

  • »
    »
    3 года назад, # ^ |
      Проголосовать: нравится +19 Проголосовать: не нравится

    I too had a terrible experience in the finals, being unable to login for > 30 minutes and was frustrated by the lack of transparency wrt the adjustment in the standings for that. Hope this year would be better.

    • »
      »
      »
      3 года назад, # ^ |
        Проголосовать: нравится 0 Проголосовать: не нравится

      Yes we do acknowledge the issues with the finals (some from our side and some with the platform used for the finals) and we suspected the same this year as well because again like the last year the team is busy on multiple contests because of the Annual TechFest and that is the reason we are conducting a single round for Coduo this year for better experience.

»
3 года назад, # |
  Проголосовать: нравится +25 Проголосовать: не нравится

It isn't ok to shift this late :(

»
3 года назад, # |
  Проголосовать: нравится 0 Проголосовать: не нравится

I see "Form link is expired" when I try to register

»
3 года назад, # |
  Проголосовать: нравится +10 Проголосовать: не нравится

Excited for this year's round. I took part last time and got to learn many new concepts as the problems were from new and diverse topics. Hope to learn more this time.

»
3 года назад, # |
  Проголосовать: нравится +5 Проголосовать: не нравится

Really looking forward to participate. Hope we'll get to solve some interesting problems.

»
3 года назад, # |
  Проголосовать: нравится +2 Проголосовать: не нравится

Excited to participate this year, got to learn new concepts in last year's contest.

»
3 года назад, # |
  Проголосовать: нравится -9 Проголосовать: не нравится

Hope you all like the contest

»
3 года назад, # |
  Проголосовать: нравится +16 Проголосовать: не нравится

excited for the round!!

»
3 года назад, # |
  Проголосовать: нравится +17 Проголосовать: не нравится

Excited for the round !!

»
3 года назад, # |
  Проголосовать: нравится +18 Проголосовать: не нравится

As a participant of last year’s contest and tester of this round,i would like to say that they really have scaled up the quality of problemsets and overall contest experience. Had a fun time testing this round :P

»
3 года назад, # |
  Проголосовать: нравится +12 Проголосовать: не нравится

Excited for the round, hopefully the problemset will be interesting!

»
3 года назад, # |
  Проголосовать: нравится +7 Проголосовать: не нравится

Excited for the Round!!

»
3 года назад, # |
  Проголосовать: нравится +16 Проголосовать: не нравится

Wishing you all the best for the round :)

»
3 года назад, # |
  Проголосовать: нравится +9 Проголосовать: не нравится

Looking forward to a great round

»
3 года назад, # |
  Проголосовать: нравится +3 Проголосовать: не нравится

Congratulations to all the top performers and thank you all the participants for such an amazing competition !!

»
3 года назад, # |
  Проголосовать: нравится +5 Проголосовать: не нравится

Hope you all liked the contest :)

»
3 года назад, # |
  Проголосовать: нравится +22 Проголосовать: не нравится

Problem "Minimum Hash" do not say solution not exist's answer is -1, which make me get lots of re or wa

»
3 года назад, # |
  Проголосовать: нравится +21 Проголосовать: не нравится

Please, proofread the statements multiple times before the contest from next time. It cost our team many wrong attempts on MNHASH just because it wasn't written that we had to print -1 if there was no valid substring. There were several typos on other problem statements too (at least I noticed the one on Tourist Queries was corrected, so that's good).

»
3 года назад, # |
  Проголосовать: нравится +10 Проголосовать: не нравится

3 days delay and still this kind of statements. Nice!! Also, what's the solution for Fitting Rectangles?

  • »
    »
    3 года назад, # ^ |
      Проголосовать: нравится 0 Проголосовать: не нравится

    Here is an AC solution for Fitting Rectangles, and here you can find a simple tool that I personally used to verify the solutions visually(it is far from perfect but was useful for me, you can simply input k followed by the output of your program into this and it should work) As for the statements, I am sorry about the mistake in the statement of Minimum Hash but I do believe that all the other statements were correct/corrected early on. We tried our best to proofread them but we overlooked that detail in the middle of the chaos of simultaneously handling multiple events under our techfest. I sincerely hope that it didn't affect the competition for a large number of participants and that you had fun regardless

    • »
      »
      »
      3 года назад, # ^ |
      Rev. 2   Проголосовать: нравится +10 Проголосовать: не нравится
      • Check the constraints and input of Fitting Rectangles.
      • Input format of Tourist queries is missing the Query input.
      • »
        »
        »
        »
        3 года назад, # ^ |
          Проголосовать: нравится +4 Проголосовать: не нравится

        The input of fitting rectangles was updated when I noticed it, the constraints could've been n <= 47 but n <= 50 holds as well and doesn't make much of a difference so I let it be. As for tourist queries, I'm sorry I forgot to mention the query format in the input format but it was provided in the statement as well

        • »
          »
          »
          »
          »
          3 года назад, # ^ |
            Проголосовать: нравится +16 Проголосовать: не нравится

          It was mentioned k >= n + 3, then how 3 3 is valid input. Anyway the problems were okay.

          Thanks for the contest.

          • »
            »
            »
            »
            »
            »
            3 года назад, # ^ |
              Проголосовать: нравится +19 Проголосовать: не нравится

            ["Standard", "Boring", "Not explained properly"] use anything you want but not "okay"

    • »
      »
      »
      3 года назад, # ^ |
        Проголосовать: нравится 0 Проголосовать: не нравится

      It wasn't mentioned in statement that we can place rectangles vertically.

      • »
        »
        »
        »
        3 года назад, # ^ |
          Проголосовать: нравится +18 Проголосовать: не нравится

        It was mentioned that the ratio of the sides has to be 1:n, it was never mentioned that you had to place the rectangles vertically or horizontally,

    • »
      »
      »
      3 года назад, # ^ |
        Проголосовать: нравится +38 Проголосовать: не нравится

      You have statements such as "nahi chala bkl" in official code?

»
3 года назад, # |
  Проголосовать: нравится +1 Проголосовать: не нравится

Tensei8869 I did not found editorial.So plz. can anyone tell me how to use binary search for this. Basically I do not know how to implement check function for binary search in this problem.

  • »
    »
    3 года назад, # ^ |
      Проголосовать: нравится +1 Проголосовать: не нравится

    Let the problem to find the subarrays in both the arrays be P. we define P(x) as the function that tells if there exists any subarrays of sizes x and x in both the arrays whose product of summations is greater than equal to k. Lets suppose I am saying that this function P is false for some variable size x. This implies that all such values (say y) that are smaller than x, the function P(y) would always give false for all of them. So this is a monotonic function and hence, binary search can be applied on the size of the subarray over which we have to check for the given condition. The condition can be simply checked using a simple Sliding Window Technique to check for all subarrays of some particular side in O(N) time complexity and hence overall code's complexity would be like O(N*logN).

»
3 года назад, # |
  Проголосовать: нравится -18 Проголосовать: не нравится

Did anybody else also misread the problem Tourist Queries. I wrongly interpreted the problem as the number of different nodes at distance v from a the queried node.