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Kinon's blog

Invitation to TOKI Regular Open Contest #23
By Kinon, history, 3 years ago, In English

Dear Codeforces community,

We are excited to invite you to TOKI Regular Open Contest #23!

Key details:

Many thanks to:

Please register and we hope you will enjoy the contest!

UPD: Contest is over!

Congratulations to our top 5:

  1. Gullesnuffs
  2. uwi

  3. Itst

  4. rama_pang

  5. yz_

Congratulations to our first solvers:

Rating has been updated.

You can upsolve the problems here.

Editorial is available in the upsolve link

Thank you for participating and see you on the next contest!

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

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

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3 years ago, # |
  Vote: I like it +59 Vote: I do not like it

Clashes with codechef Lunchtime.

Move a day later maybe if possible (28th looks completely free as of now).

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3 years ago, # |
  Vote: I like it +13 Vote: I do not like it

Niceee!! Will be looking forward to it <3 :punch: :sunglasses: JvThunder yz_ MetalPower CyberSleeper Zanite Edbert.H gansixeneh Bryannoel :fanfare:

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

Do you guys have any plan to add contest reminder on google calander? It's hard for me to keep track of the contests without it :(

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3 years ago, # |
  Vote: I like it +22 Vote: I do not like it

Fun fact about the author, might give you an idea of how the problems are gonna be :)

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3 years ago, # |
← Rev. 4   Vote: I like it +14 Vote: I do not like it

Thanks for the great contest! I just want to give abit of feedback.

I think testdata for D is super weak. With only 20 tests, I feel that the problem is very easily able to be scammed with heuristics and other weird strategies.

I think one of the participants (Submission #339419) coded the editorial's solution without attaching the extra node (greedily remove cliques) and it ACed.

I think you should reduce limits and give multitests instead.

Edit: ok it turns out that greedily removing cliques actually works using similar analysis as the editorial. so now im more confused on why the editorial didnt just talk about the more natural solution of removing cliques...

empirically removing cliques seems to only use 60k queries

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    3 years ago, # ^ |
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    Why does greedily removing cliques work? Isn't the minimum clique equivalent to 4 teams?

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      3 years ago, # ^ |
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      we can handle that with extra $$$3$$$ queries anyways

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    3 years ago, # ^ |
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    I think you meant adding cliques

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

not able to see English problem statements while upsolving, tried viewing problem statements in mobile, laptop(chrome, brave browser)

upd: Iam able to view now

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3 years ago, # |
  Vote: I like it +8 Vote: I do not like it

C's author solution is beautiful <3, I wonder how many were able to think of it, I iterated over bitmask.

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