darkkcyan's blog

By darkkcyan, history, 20 months ago, In English

Hello Codeforces!

We are glad to invite you to take part in mirror round of the first round of VNOI Cup, which will take place at 13:00 UTC, on this Saturday, 18th June, and it is hosted on our builtin platform — VNOJ!

round1-poster

If you are Vietnamese and qualified according to these rules mentioned on this post, please consider taking part in the official round!

VNOI Cup is a Competitive Programming competition held by VNOI (Vietnam Olympiads in Informatics community), which is a non-profit organization, by Vietnamese competitive programmers, for Vietnamese competitive programmers. Our aim is to support the growth of competitive programming in Vietnam, and we hope that this competition is one of the things that follows this aim!

There are 3 elimination rounds and a Final round in this competition. In this elimination round, there will be 5 problems to solve in a duration of $$$150$$$ minutes. The problem statements for the mirror rounds will be in English. We have worked our best to make sure that the round have a good range of difficulties, so we welcome everybody to join this mirror round!

Remember that the round will take place at 13:00 UTC, on this Saturday, 18th June, and you can take part in the round via this link!

The next two rounds will also be close by, so be prepared!

  • Round 2 will be held on 25th June.
  • Round 3 will be held on 2nd July.

Hope you enjoy the rounds and thank you for participating! <3

  • Vote: I like it
  • +147
  • Vote: I do not like it

»
20 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Auto comment: topic has been updated by darkkcyan (previous revision, new revision, compare).

»
20 months ago, # |
  Vote: I like it +10 Vote: I do not like it

Will there be subtasks and partial scores ?

  • »
    »
    20 months ago, # ^ |
      Vote: I like it +8 Vote: I do not like it

    There will be subtasks. To get the score for one subtask, you must solve every tests in that subtask correctly.

    Thanks, I will update this fact in the post soon!

»
20 months ago, # |
  Vote: I like it +10 Vote: I do not like it

Highly recommend you guys to take part in the mirror, the problems are superb!

»
20 months ago, # |
  Vote: I like it 0 Vote: I do not like it

What’s the approximate difference of problems?

  • »
    »
    20 months ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    You mean difficulties? :))

    I don't want to spoil too much about the details, but there are easy, and there are challenging problems as well. We welcome everyone to come and try out our challenges!

    • »
      »
      »
      20 months ago, # ^ |
      Rev. 2   Vote: I like it 0 Vote: I do not like it

      Oh yeah, difficulty. Was so tired that started confusing the words :)

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

Why this website is having the same UI as DMOJ?

  • »
    »
    20 months ago, # ^ |
      Vote: I like it +12 Vote: I do not like it

    Because of the powerfulness of the Open Source god?

»
20 months ago, # |
Rev. 2   Vote: I like it +11 Vote: I do not like it

Last problem was a bit tricky, i wish there was more time :( Will we be able to upsolve the problems ?

  • »
    »
    20 months ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    Yes. But please wait for us to finalize the result first! We will publish the problems shortly!

»
20 months ago, # |
  Vote: I like it +13 Vote: I do not like it

Can you take a quick minute to leave us a review? Thank you so much!

»
20 months ago, # |
  Vote: I like it +13 Vote: I do not like it

I think this was a good contest. The problem statements were clear, and most were relatively short. All the problems were good practise.

»
20 months ago, # |
  Vote: I like it +8 Vote: I do not like it

From VNOI with love:3

»
20 months ago, # |
  Vote: I like it 0 Vote: I do not like it

I enjoyed the problems though I wonder if there is anything better for E than doing cheese $$$O(N^2/64)$$$ knapsack with bitsets

  • »
    »
    20 months ago, # ^ |
      Vote: I like it +10 Vote: I do not like it

    You can speed up the subset sum part by grouping components with same size. The tricky part is the case where we need to partition one such component into two parts. We can use the divide and conquer trick (similar to 1442D - Сумма) and obtain an $$$O(N\sqrt{N}log{\sqrt{N}})$$$ solution.