vito1036's blog

Croatian Open Competition in Informatics (COCI) 2023/2024 — Round #2
By vito1036, history, 12 months ago, In English

Hi everyone!

The second round of COCI will be held this Saturday, December 2nd at 14:00 UTC. You can access the judging system here. If you are not familiar with COCI contest format, we encourage you to read the announcement.

The round was prepared by ToniB, Agnus, fbabic, mlicul and me.

Feel free to discuss the problems in the comment section after the contest ends.

Hope to see you and good luck!

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12 months ago, # |
  Vote: I like it +19 Vote: I do not like it

why is there a bitset in tags ?

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12 months ago, # |
← Rev. 2   Vote: I like it +19 Vote: I do not like it

The judge and https://hsin.hr/coci/ conflict about the start time? It seems the judge is crotia time and the announcment page is UTC, but both say 14.00. Can you clarify this?

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    12 months ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    +

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    12 months ago, # ^ |
    ← Rev. 2   Vote: I like it +11 Vote: I do not like it

    Thanks for the info! The judge starting time is wrong. The round will start at 14:00 UTC. UPD: it's fixed now.

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12 months ago, # |
← Rev. 2   Vote: I like it +17 Vote: I do not like it

Reminder: the contest starts in one hour.

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12 months ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

Feedback:

  • Task 1: Meh
  • Task 2: Meh
  • Task 3: Cute task, enjoyed it.
  • Task 4: A bit standard, but ok. Perhaps this should have had slightly less points?
  • Task 5: Again, a bit standard but a decent educational problem.

Overall, problems were good quality and educational, kind of like old style cf problems. The contest would have been more enjoyable if either task 1 or task 2 was replaced by a harder problem.

Edit: Also, the tests for task 3 might be a bit weak. My first submission had a very critical bug (which was not dependent on n) but it passed all test cases of the first 3 subtasks and 13/15 test cases of the last subtask.

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12 months ago, # |
  Vote: I like it +19 Vote: I do not like it

This is the first time I AK an OI contest, it feels amazing !

I feel problems are a little bit easier than usual, but I still enjoyed the contest, well done.

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12 months ago, # |
  Vote: I like it +2 Vote: I do not like it

where can i upsolve?

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12 months ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

Problems was very good.But I solved 1-st problem full.other problems I got some subtasks.Can you share your idea for problems?

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

There is $$$O((n+q)\log{}n)$$$ solution for Dizalo...

Hint
Code
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    12 months ago, # ^ |
    ← Rev. 2   Vote: I like it +13 Vote: I do not like it

    You can do it online with the same complexity.

    Code
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      10 months ago, # ^ |
        Vote: I like it +8 Vote: I do not like it

      You will get a RE because you erase the end of a set.(in line.77). Or please explain why.

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        10 months ago, # ^ |
        ← Rev. 2   Vote: I like it 0 Vote: I do not like it

        Oh, i am stupid, now i understand, sorry.

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        10 months ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        The if statement on line 69 has a condition that will always be true, perhaps this caused the confusion.

        I'm not sure why I put it there, since it is completely redundant. Thanks for pointing this out (the code is edited now).

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12 months ago, # |
  Vote: I like it -24 Vote: I do not like it

asdasdasd

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