Cauchico's blog

Helvetic Coding Contest 2024 — Online Mirror
By Cauchico, history, 7 months ago, In English

Hello Codeforces!

Back from the dead, we'd like to invite you to the online mirror of the Helvetic Coding Contest, Switzerland open championship! You can find past mirror from 2019, 2018, 2017, and 2016.

The Helvetic Coding Contest used to be held yearly at EPFL. This year, the Polympiads association is bringing it back alive! The contest itself took place on April the 13th, but the online mirror is scheduled on Saturday, 4th of May, 09:05 Swiss time. The duration is 4:30.

Rules:

  • you can participate in teams or individually with a single computer (1-3 people),

  • standard ACM-ICPC rules (no hacking),

  • the contest is not rated,

  • if you have participated in the onsite contest, please do not participate in the mirror.

Contrary to what the mirror's date might lead you to believe, this year's theme is Harry Potter. It features 7 series of 3 related tasks with increasing difficulty (easy/medium/hard). Note that we do not guarantee that all problems are solvable using python.

Thanks a lot to:

UPDATE: Editorial is out, also available as a PDF. Thanks all for participating!

UPDATE 2: Congratulations to the winners who solved all 21 subtasks:

  1. thinking: Ormlis, Mangooste
  2. Captain take me!: crazy_sea, A_zjzj, 275307894a
  3. japan406364961: Nyaan, kotatsugame, risujiroh
  4. Qingyu Fan Club: xinyoudui, GapGapGap, InfiniteStarlight
  5. Idea Generators Club: tedi_2.0, Denisov, Valera_Grinenko
  6. 244mhq
  7. jiangly

UPDATE 3: Also huge congratulations to the winners of the onsite round (no prewritten code or Internet access was allowed, so the conditions were a bit different):

  1. Felt smart (might un-participate later) — 20 subtasks
  2. Nameless Silly Moon — 18 subtasks
  3. ***IsEvil? — 17 subtasks
  4. Breakfast Master Toaster — 16 subtasks
  5. Hairy Stofler — 16 subtasks
  6. thethingswedoforpizza — 15 subtasks
  7. huchibuchi — 15 subtasks

We hope you enjoyed the problems, please share your thoughts in comments!

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7 months ago, # |
  Vote: I like it +58 Vote: I do not like it

Cauchico orz

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7 months ago, # |
  Vote: I like it +9 Vote: I do not like it

move closer, don’t spoil your eyes

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7 months ago, # |
  Vote: I like it -143 Vote: I do not like it

Contrary to what the mirror's date might lead you to believe, this year's theme is Harry Potter

Harry Potter is a controversial series, a poor choice by the organizers :|

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    7 months ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    Harry potter is one of the most famous series of all time. I have read every book atleast twice and seen each movie >= 5 times. Thats how good it is. Stop bring politics into everything. NOBODY CARES.

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      7 months ago, # ^ |
        Vote: I like it +3 Vote: I do not like it

      Harry potter is one of the most famous series of all time

      ... and RCB is the most supported IPL team of all time. Popularity of some entity in the modern day only indicates the number of midwits the creators of said entity managed to brainwash through advertising.

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      7 months ago, # ^ |
        Vote: I like it +30 Vote: I do not like it

      When we're talking about things with such immense cultural value and influence as Harry Potter, we're not really bringing politics into it. Because it already is there, whether we care about it or not.

      The series certainly carries a particular messaging on what's right and what's wrong, and since it is targeted at younger audience, it is also very likely to at least to some extent shape their values and worldview.

      It is of course up to us whether to agree or to disagree with the ideas that J. K. Rowling put into the book, and I personally would be pretty much against canceling such a monumental work just due to a disagreement with its messaging. But turning a blind eye to its political nature and pretending that it's just not there is also a very questionable, and a somewhat dangerous act. Being conscious about what we promote and what political ramifications it carries is the least we can and must do.

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

    Please separate the art from the artist.

    EDIT: Oh I thought this was about JK Rowling's questionable comments. Well, still these aren't nearly serious enough things to justify boycotting such a famous series.

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    7 months ago, # ^ |
      Vote: I like it +21 Vote: I do not like it

    Any monumental series would be controversial in particular social circles. Sending a general link to the page doesn't help at all, unless you at least outline which particular messaging of the series you disagree with so much that you think it deserves to be boycotted. On a side note, if we keep being too nitpicky about what series we theme stuff around, we will end up in a very grey and boring world, because it is the only way to remain totally uncontroversial.

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

      To be specific, I find it odd that a competition with the following eligibility policy on their website

      Eligibility: Every person, irrespective of age, gender, nationality, or any other factor, is welcome to participate.

      chosen a theme for itself that was well-known for the mistreatment of minorities. In retrospect, I agree that my message was likely unclear to people out of the loop.

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7 months ago, # |
  Vote: I like it +26 Vote: I do not like it

As an onsite participant, the problems are good!

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

What is difficulty level of problems?

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    7 months ago, # ^ |
      Vote: I like it +45 Vote: I do not like it

    Each problem has 3 versions (subtasks) with increasing difficulty (easy/medium/hard), therefore I hope there is something interesting to solve for everybody!

    The easiest task is probably around Div2A, while the hardest task is probably around Div1E.

    The contest as a whole is easier than Universal Cup rounds or strong ICPC regionals or World Finals. I would expect a World Finals medalist team to solve everything in about 3 hours, but my perception might not be spot on.

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7 months ago, # |
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Which one do you suggest? Participating as a team or individually?

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    7 months ago, # ^ |
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    I think participating as a team is better,because it is fun and you can solve problem quickly.

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7 months ago, # |
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Are you related to the font of Helvetica?

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

    Helvetica is a widely used sans-serif typeface developed in 1957 by Swiss typeface designer Max Miedinger and Eduard Hoffmann.

    Basically "helvetic" is a fancy synonym for "swiss".

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7 months ago, # |
← Rev. 3   Vote: I like it 0 Vote: I do not like it

Cauchico .

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7 months ago, # |
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Is there age limit when you participate onsite???

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

Wonderful set of problems, although i could only solve B3.

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7 months ago, # |
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how to solve c2,c3?

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    7 months ago, # ^ |
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    You ca share C1 approach.

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

      first make array after go to current node , and check whether the exist odd length on either side then ron wins . (2 3 1 we are standing on three , both side we have odd moves so ron will win)

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    7 months ago, # ^ |
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    Think about a matching on the graph. If you start from an unmatched node what happens?

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      7 months ago, # ^ |
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      Isn't matching too much for such a problem?

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        6 months ago, # ^ |
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        No, because most problems about moving on a graph use it.

        Here is a classical one:

        Q: A and B take turns moving on a graph and cannot visit the same node twice. The one who cannot move loses. Who wins? A: if the graph has a perfect matching, B wins; otherwise, A wins.

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    7 months ago, # ^ |
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    Spoiler
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      7 months ago, # ^ |
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      I understood most of the part, but can you please explain:

      If dpx=0 --> losing state --> dpp = dpp−1

      Why decrementing the dpp??

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        7 months ago, # ^ |
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        Because after changing the root, x will not be a child or p anymore, so it can't use x anymore as a way to win, so the number of children that p can use to win decreases

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7 months ago, # |
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When I passed D1, I couldn't believe that I got the first blood!

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7 months ago, # |
  Vote: I like it +11 Vote: I do not like it

Do these problems have an editorial? Or can we watch other participants' codes? Thanks!

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

W contest!

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7 months ago, # |
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Auto comment: topic has been updated by Petr (previous revision, new revision, compare).

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

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

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7 months ago, # |
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egg

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7 months ago, # |
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Auto comment: topic has been updated by Petr (previous revision, new revision, compare).

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

High Quality tasks!!!

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7 months ago, # |
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Codeforces Helvetic Contest 2024

Detailed Video Tutorial B1 + B2 + B3

https://youtu.be/1s9NN3D3TWY

(Language => Hindi)

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7 months ago, # |
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Weak test cases on F1 where Quaffle doesn't move at all! However it does on F2 which confused me a lot :(

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7 months ago, # |
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As an onsite participant, the problems are good!

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

for people wondering the onsite winner team was adamant and mango_lassi from eth zurich :)

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7 months ago, # |
  Vote: I like it -13 Vote: I do not like it

Can rainboy tourist nor start solving problem J together? For the entire month provide advice and support, it's really important

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7 months ago, # |
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Will the rating of problems in this contest be updated?

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6 months ago, # |
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I rarely do these kinds of mirror contest as the major problem for me is that the statements always make me hard to understand. I wish there are some explanations at the end of each problems, but they mostly don't have that.

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6 months ago, # |
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C and D >>>>>>G Anyone agrees ?

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5 months ago, # |
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Congratulations winners!!

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