maroonrk's blog

By maroonrk, history, 8 days ago, In English

We will hold AtCoder World Tour Finals 2024.

List of Finalists:

AtCoder IDCodeforces ID
zhoukangyangorzdevinwang
StonefeangRadewoosh
ecnerwalaecnerwala
touristtourist
heno239heno239
ksun48ksun48
jianglyjiangly
apiadjqdai0815
endagorionEndagorion
Um_nikUm_nik
noshi91noshi91
ugly2333ugly2333

The point values will be 700-1000-1500-2000-2000. We don't freeze the standings in the contest.

AtCoder World Tour Finals 2024 is an international onsite contest. We have invited top-runners of AtCoder Race Ranking 2023 to Tokyo. Since cnnfls_csy (8-th in the race) couldn't come to the Finals, ugly2333 has advanced as the runner-up. For more details, please visit this page (https://info.atcoder.jp/more/contents/awtf/2024) (this is under construction, though).

Note that, unlike last year, the mirror contest is Unrated and the standings is hidden.

About Streams

On the contest day, we will stream the contest on our YouTube channel. This year we have a special guest Petr! I and he will be watching the contest and discuss problems. Obviously, Finalists should not watch the stream during the contest. The mirror contest participants can watch it since there's no way to prevent it. This is why the mirror is Unrated and the standings is hidden.

And last but not least, we had set up a "confessional booth" this year. This idea comes from the chess tournaments (example) — a room where you can go during the contest (one at a time, obviously) and say something to be shown on stream. This is a new attempt and we hope it makes the stream more interesting!

We are looking forward to your participation (in the mirror or stream)!

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8 days ago, # |
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Auto comment: topic has been updated by maroonrk (previous revision, new revision, compare).

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8 days ago, # |
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In the picture on the top of the website, why the username is "maroonk"?

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8 days ago, # |
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orzdevinwang will win the world tour!

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8 days ago, # |
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Interactive table of the finalists with their ratings and previous AtCoder World Tour Finals stats:
https://cphof.org/advanced/atcoder_wt/2024

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8 days ago, # |
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Why is the mirror unrated :(

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    8 days ago, # ^ |
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    Obviously, Finalists should not watch the stream during the contest. The mirror contest participants can watch it since there's no way to prevent it. This is why the mirror is Unrated and the standings is hidden.

    I know, it was a long post and you are tired

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8 days ago, # |
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Will the mirror contest's standing be released after contest?

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8 days ago, # |
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We are waiting for the AWTF2024 Finalist Profile to be updated!

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7 days ago, # |
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We are having a network issue and the contest is delayed. We are gonna start when we can, and also announce it here. 1hr delay is tentative, it can start earlier.

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    7 days ago, # ^ |
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    They've just realized that A is also unsolvable and are preparing a new one instead.

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      7 days ago, # ^ |
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      They've just realized that A is solvable and are preparing a new one instead.

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    7 days ago, # ^ |
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    The contest will start at 13:45 (in 3 minutes).

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7 days ago, # |
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The contest will start at 13:45. Sorry for inconvenience.

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7 days ago, # |
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The contest started. We also restarted the Stream, the URL is https://www.youtube.com/watch?v=uajgh54TRu8

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7 days ago, # |
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Problem D is almost same as https://codeforces.com/contest/1637/problem/H xD..

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7 days ago, # |
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Geothermal congratulationsssssssssssssssssssssss

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7 days ago, # |
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Why award ceremony was not streamed??

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    7 days ago, # ^ |
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6 days ago, # |
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Hi, is there any way to view finalists code? I can see all the submissions in open contest but not of finalist.

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6 days ago, # |
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I looked at several solutions to B (example: https://atcoder.jp/contests/awtf2024-open/submissions/55473500) and they all looked equivalent to the formula $$$f(S)$$$ from the editorial.

Is there a way to come up with this formula without assuming $$$f$$$ is the sum of some quantity over all cells of the Young diagram and solving for that quantity? Or a way that doesn't even involve interpreting $$$S$$$ as a Young diagram?

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    5 days ago, # ^ |
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    My solution was pretty different (posted here). I would be interested in knowing if

    • there's a way to skip the step of printing out values and guessing the pattern to optimize from $$$O(N^2)$$$ to $$$O(N)$$$
    • there's an easier way to see its equivalence to the official solution
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6 days ago, # |
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hos.lyric I am reading your editorial, and in the last section, I am confused about why the shape condition holds after swapping rows $$$l$$$ and $$$r$$$. Suppose $$$x'$$$ is the good permutation associated with $$$U(K)$$$ prior to the swap. Since $$$l$$$ and $$$r$$$ are not necessarily adjacent in $$$x'$$$, isn't it possible that $$$x'$$$ is no longer good after swapping their positions?

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    4 days ago, # ^ |
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    Thanks for pointing out, I think you are correct. Perhaps we need to rotate the rows $$$l,\ldots,r$$$ instead of swapping $$$l$$$ and $$$r$$$. Now to check [Property 2] we will need some more facts about $$$f$$$: in fact $$$f[x]$$$'s are in total order and unimodal (I think I had proven them before but didn't included in the editorial after I (mistakenly) simplified it). I'm trying to rewrite the proof.