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Morphy's blog

CC Hello 2021 Long Challenge
By Morphy, 4 years ago, In English

Hello 2021!

We invite you to participate in CodeChef’s January Long Challenge, this Friday, 1st January, from 15:00 IST onwards. The contest will be open for 10 days. We are introducing a brand new Division 3

If you have some original and engaging problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here.

Joining me on the problem setting panel are:

Prizes:

Top 20 performers in the Indian category and top 10 performers in the Global category will get CodeChef laddus, with which the winners can claim cool CodeChef goodies. First to solve each problem except challenge — 100 laddus. Know more here

The video editorials of the problems will be available on our YouTube channel as soon as the contest ends. Subscribe to get notifications about our new editorials.

Good Luck!
Happy new year!

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Comments Comments (28)
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4 years ago, # |
  Vote: I like it +41 Vote: I do not like it

You forgot to mention the rating division changes. Now 2000+ rated are div 1, not 1800.

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4 years ago, # |
  Vote: I like it 0 Vote: I do not like it

I hope this new rating division system will do great.

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4 years ago, # |
← Rev. 2   Vote: I like it +11 Vote: I do not like it

Feature request for Codechef : Please make test cases available after every contest.CodeChef_admin

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4 years ago, # |
  Vote: I like it +58 Vote: I do not like it

CodeChef's ingenious solution to lack of problem proposals: create a whole new division, requiring even more problems.

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    4 years ago, # ^ |
      Vote: I like it +14 Vote: I do not like it

    2-3 cakewalks/simple for div3 would not be an issue.

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4 years ago, # |
  Vote: I like it -24 Vote: I do not like it

Codechef should also add this magic button. So, At least we can enjoy Colour Change for 10 Days there also.

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    4 years ago, # ^ |
      Vote: I like it +11 Vote: I do not like it

    Let them focus on their slow servers first !!

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4 years ago, # |
  Vote: I like it +4 Vote: I do not like it

Very unbalanced problems in division 2 :(

Spoiler
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    4 years ago, # ^ |
      Vote: I like it +2 Vote: I do not like it

    huh...first time?

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      4 years ago, # ^ |
        Vote: I like it +9 Vote: I do not like it

      My disappointment is immeasurable, and my day is ruined :(

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        4 years ago, # ^ |
        ← Rev. 2   Vote: I like it +18 Vote: I do not like it

        It's not unbalanced, just people on CC are not used to the difficult problems. You aren't supposed to solve more than 5 problems after a lot of struggling unless you are at least high expert/low candidate master on CF. The ideas in CodeChef Long Challenge problems from 6 to 10 are at least D2D and even harder than that.

        You aren't given 10 days for no reason. Just try utilizing your time as well as you can, research topics online, practice problems on other judges alongside it and you may happen to get an idea which solves the harder problems easily.

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4 years ago, # |
← Rev. 2   Vote: I like it +3 Vote: I do not like it

How is the long cheating challenge going on ? :p

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    4 years ago, # ^ |
    ← Rev. 2   Vote: I like it -8 Vote: I do not like it

    Yeah, I am pretty much disappointed :(
    1. Firstly, by the unbalanced problemset (Solving more than 2 problems seems pretty difficult for anyone below CM on codeforces)
    2. And by the amount of plagiarism going on. There's no point in participating, since the rank (and rating change) depends on the number of solves for each problem and no other penalty. You can argue that by participating and solving those problems, improvement occurs within you, but if that is the only purpose of long contests, then they should simply make it unrated

    Like I said above, My disappointment is immeasurable, and my day is ruined :(

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      4 years ago, # ^ |
        Vote: I like it +19 Vote: I do not like it

      1. We can discuss the difficulty of the problemset after the contest finish. For now all I can say is that I feel it is not very unbalanced, there is even subtasks to make the transition smooth. Also don't underestimate CMs!

      2. Probably I'm not the most appropriate to answer that, when I used to take part in contests I didn't cared about cheating, I just focused in the problemset and tried to do my best. Codechef has some meassures against cheating, let's hope the MOSS can catch many of those cases, also two longs ago one guy was able to close some of the cheating-sources, the leaked solutions and its authors should be banned. Rating can be motivating for some users, and coders at the top (at least top 1000) are unaffected by plagiarism, it would be weird to make it unrrated only for div3 ...

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    4 years ago, # ^ |
    ← Rev. 2   Vote: I like it +8 Vote: I do not like it

    How is commenting on the ALL the blogs of long challenge about cheating going to help? There are already many blogs posted about the YT channels/similar submissions/telegram groups and I am pretty sure the admins(CF and CC both) are looking for some means to stop that. But commenting again and again (and even tagging the admins) doesn't make the whole matter more irritating for the people who are actually creating these contests and maintaining these platforms for us?

    I am a problemsetter for the problem WIPL of long challenge, and you know what makes me more sad than seeing the various videos of the solution? : seeing all the blogs literally saying "All the team's work went in vain".

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      4 years ago, # ^ |
        Vote: I like it +1 Vote: I do not like it

      ngl that was a pretty difficult problem at least for me but its the best I learned a lot from it , you are awesome for making such a specimen question One of my favorite that's for sure

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4 years ago, # |
← Rev. 2   Vote: I like it +1 Vote: I do not like it

Hi, is there a way for me to report on users that are publishing/trying to sell solutions while the contest is still ongoing?

I really enjoy the Long Contests and it is really sad to witness users trying to game the rating system. Also sad with the CF Goodbye massive community cheat...

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    4 years ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    "Ideally, if you want to report that some users have cheated, or if you want to appeal against having been caught for plagiarism, you should only send an email to help@codechef.com, and wait for a few weeks to get a reply." : admin

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4 years ago, # |
← Rev. 2   Vote: I like it +8 Vote: I do not like it

The video editorials to the problems are uploaded on Youtube. And the editorials can be found here.

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    4 years ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    Please run a system test like codeforces first and then change rating. 135/206 submissions in div 2 tilesquares are same. Similarly, 197/220 are same in Div 3. Just imagine the amount of plagiarism.

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4 years ago, # |
  Vote: I like it +29 Vote: I do not like it

Tomorrow I'm going to livestream the solution for ARCRT — link. As the hard part of the problem was implementing LCT + component sizes, I'm going to be implementing this during the stream (with treaps as splay trees are more annoying). If you have never implemented a LCT by yourself, you might find this interesting.

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4 years ago, # |
  Vote: I like it +63 Vote: I do not like it

Congrats to the winners!

Div 1.

  1. BigBag
  2. Oleg
  3. krijgertje
  4. jijiang
  5. Itst_boyfriend
  6. Marckess, first in latin-america
  7. run_timeterror, first in india

Div 2.

  1. xyr2005
  2. watercup
  3. sharansh12
  4. aert
  5. Jughead
  6. FallingStar
  7. ac1go

Also take a look of what happened Behind the scenes

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