KAN's blog

By KAN, 3 weeks ago, translation, In English,

Hi all!

This weekend, at Sep/23/2018 16:05 (Moscow time) we will hold Codeforces Round 512. It is based on problems of Technocup 2019 Elimination Round 1 that will be held at the same time.

Technocup is a major olympiad for Russian-speaking high-school students, so if you fall into this category, please register at Technocup 2019 website and take part in the Elimination Round.

Div. 1 and Div.2 editions are open and rated for everyone. Register and enjoy the contests!

The Elimination Round authors are Ajosteen, BledDest and adedalic. Thanks to FCB1234 who authored the last problem for div. 1 round and arsijo for his help in coordination. This round would also be not possible without the help of our testers: winger, Um_nik, AlexFetisov, Denisson, thank you so much!

Have fun!

Div. 2 and the Elimination Round will feature 7 problems, preliminary costs are
250 — 500 — 750 — 1500 — 2000 — 2500 — 3000.

Div. 1 will feature 5 problems, preliminary costs are 500 — 1000 — 1500 — 2000 — 2500.

The round is over, congratulations to the winners!

Technocup 2019 - Elimination Round 1

  1. 300iq
  2. antony191
  3. voidmax
  4. karasek
  5. ushakov.fedor

Codeforces Round #512 (Div. 1, based on Technocup 2019 Elimination Round 1)

  1. fjzzq2002
  2. mcfx
  3. yjq_naiive
  4. j_______________________
  5. volamtruyenkyii

Codeforces Round #512 (Div. 2, based on Technocup 2019 Elimination Round 1)

  1. Chair_man_Xi
  2. icecuber
  3. yp155136
  4. xjd0623
  5. liyingyan7

The analysis is published.

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By KAN, 6 months ago, translation, In English,

Hi everyone!

Tomorrow, on the April 29, 2018, at 13:05 UTC we are holding the third round of VK Cup 2018 championship. This is the final online round, the next round is the final round in which top 20 teams from this round advance.

At the same time with the official round, we are holding parallel rounds for both divisions. Join them and see if you can beat top Russian-speaking teams! Top50 in the "Div1 Edition" contest will get t-shirts.

All rounds are rated, their duration is 2.5 hours.

The authors of the problems are Zlobober, Endagorion and me. Thanks qwerty787788 and gritukan for their great help in round preparation!

Good luck!

Congratulations to winners!

  1. V--o_o--V, LHiC — solved all problems, two problems ahead the runner-up!
  2. senek_k, demon1999
  3. sinesight, SpyCheese
  4. Melnik, hloya_ygrt
  5. egor_bb, Nikitosh

Mirror for the first division:

  1. fateice
  2. Petr
  3. tourist
  4. BudAlNik
  5. fjzzq2002

Mirror for the second division:

  1. _ChenKerui
  2. Hayven
  3. poisonous
  4. Gold_Three_Fat
  5. laofudamajiang

The editorial is here, thanks all for participation!

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Announcement of VK Cup 2018 - Round 3
 
 
 
 
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By KAN, 6 months ago, translation, In English,
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By KAN, 6 months ago, translation, In English,

Hi everyone!

digital resistance

Tomorrow, on the April 25-th, 2018 at 17:35 UTC we are holding Codeforces Round #476 (Div. 2) [Thanks, Telegram!]! The round will be rated for the second division participants, members with higher rating can take part out of competition.

I give the floor to MikeMirzayanov to announce the round:

This round opens a series of thanks-rounds to those who significantly supported Codeforces in the crowdfunding campaign for the 8th anniversary. Although Telegram is not explicitly present on the list of donators, for us this is the first and most important friend. We express our gratitude to Telegram and personally to Pavel Durov for the constant support and send regards from programming contest community. Now that the medieval inquisition against Telegram and all the free Internet has been declared in our country, I admire and express support for Pavel's principled position on protecting our rights and freedoms. Thank you, Telegram!

I join the thanks to Telegram, and also want to thank neckbosov and Livace who helped me with the problems for the round. Also many thanks to gritukan, GreenGrape and 300iq for their help in round preparation, and arsor for translation.

Good luck!

Congratulations to winners!

Div. 2:

  1. Akylbeek — solved all problems!
  2. aho_kolyasik
  3. reeWorld
  4. 16bit075
  5. teamskiy

Div. 1:

  1. uwi
  2. quailty
  3. retrograd
  4. I_love_Maria_Ivanova
  5. Adalbert

The analysis is here.

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By KAN, 7 months ago, translation, In English,

Hi!

Tomorrow, on March 24-th, 2018 at 15:35 UTC we will host the second round of VK Cup 2018 — a programming tournament for Russian-speaking youth. 450 teams that were the best in the first round and the first wild-card round will compete tomorrow. The top 100 teams will advance to the third round directly and get a tournament t-shirt, while the others will have one more chance in the second wild-card round.

For English-speaking community as well as for those who haven't advanced to the second round or haven't participated in VK Cup 2018, we will host parallel Codeforces round for both divisions, as usual. Feel free to take part!

Please note that the tournament is for Russian-speaking people. If you don't speak Russian, you must not compete in the VK Cup round, register for the parallel round instead. Otherwise it is considered as a flagrant violation of rules and might be subject to disqualification and Codeforces ban. Please respect the organizers.

VK Cup 2018 Round 2 and the round for the first division will have six problems each, the second division round will have five of them.

The authors of the problems are cyand1317, skywalkert, Claris and me. Also many thanks to fcspartakm, Tommyr7 for their help in preparation and PavelKunyavskiy, winger, AlexFetisov, Errichto, vepifanov, immortalCO and qwerty787788 for testing the problems! Last but not least, huge thanks to gritukan for his great help in coordinating and testing the round!

Good luck!

The editorial is published!

Congratulations to the winners!

VK Cup Round 2:

  1. LHiC, V--o_o--V — solved all problems!
  2. egor_bb, Nikitosh
  3. I_hate_ACM, Golovanov399
  4. AllCatsAreBeautiful, arsijo
  5. aid

Div. 1:

  1. Um_nik
  2. Radewoosh
  3. ikatanic
  4. FizzyDavid
  5. OO0OOO00O0OOO0O00OOO0OO

Div. 2:

  1. ltf0501
  2. Hyperbolic
  3. yongshiboshi
  4. emengdeath
  5. lmhoang

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Announcement of VK Cup 2018 - Round 2
 
 
 
 
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By KAN, 7 months ago, In Russian,
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By KAN, 7 months ago, translation, In English,

Hi!

Tomorrow, on March 17th, 2018, at 15:35 UTC the first Wild-card Round of VK Cup 2018 will be held. Along with it we will host a parallel unofficial round in which everyone can take part.

The rounds will use special rules, the rounds will be unrated. The problems were prepared by Codeforces team: fcspartakm, MikeMirzayanov and me. Thanks to Vovuh, GreenGrape, neckbosov, glebodin and gritukan for testing the round and their help to make the round better!

The detailed rules will be added to this post around 30 minutes before the start. There will be 24-hours open hacks phase after the round, like in Codeforces Educational Rounds.

Round rules:

The round will be almost usual contest with ACM ICPC rules. There will be 10 problems for 2 hours. During the round your solutions will be tested on some basic tests, they should be much stronger than usual pretests. After the round you will have 24 hours to find tests against other participants' solutions, this part is the same as in Educational rounds. After that we will add all succesful hacks and our tests and rejudge all submissions. Then the results will be final.

The main difference between ACM ICPC rules and this round is the following rule.

You should submit each problem in a unique programming language. Different compilers of same language are considered the same language. For example, GNU G++, GNU G++ 11, GNU G++ 14 and MS C++ compilers are C++ language. Thus, you are not only to solve problems, but also try different and new for you languages. We don't think you know 10 languages, we hope that you will quickly learn some basic syntax.

Formally, the following check is performed when you submit a task:

  • If there is at least one submission in queue or submission that passed at least one test for this problem in another language, your solution will be ignored. Thus, if your program passes at least one test, you can only solve this problem using this language.
  • If there is at least one submission in queue or submission that passed at least one test for another problem in same language, your solution will be ignored. Thus, you can't use a language for more than one problem.

Remember that you can view filter status of some other round by language and view submissions in a specific language. Also, you can view examples of codes in any of the supported languages on the table below. Also, the table contains the groups of compilers considered the same language.

You can use "custom invocation" tab to run a solution if you don't have the compiler locally.

Группа языков Языки программирования / компиляторы Примеры
C GNU C, GNU C11 10903473, 17029870
C++ GNU C++, GNU C++11, GNU C++14, GNU C++17, MS C++, etc. 23794425, 5456501
C# Mono C#, MS C# 3195513, 3794163
D D 5482410, 2060057
Go Go 7114082, 21366098
Haskell Haskell 455333, 1668418
Java Java 8 25491359, 23678167
JavaScript V8 35963909, 35681818
Kotlin Kotlin 25779271, 25204556
OCaml OCaml 6157159, 1281252
Pascal Delphi, FPC, Pascal.NET 1275798, 1259434
Perl Perl 2519448, 1277556
PHP PHP 413942, 35875300
Python Python 2, Python 3, PyPy2, PyPy3 35883730 (Py2), 36179112 (Py3)
Ruby Ruby 1837970, 1289551
Rust Rust 25180002, 35652442
Scala Scala 35847980, 2456025

The main rules of ACM ICPC contest: each problem can either be completely solved (when all tests are passed), or not solved. The participants are ranked by the number of solved problems, in decreasing order, in case of a tie they are ranked by penalty time. The penalty time is the sum among all problems the time in minutes that had passed between the start of the round and the moment the problem got solved, plus 20 minutes for every rejected submission. Note that the problems are not arranged by difficulty. Also, you can resubmit a solution even if it passed all tests, because there will be more tests after the open hacks.

Good luck!

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By KAN, 7 months ago, In Russian,
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By KAN, 7 months ago, translation, In English,

931A - Friends Meeting

At first understand the fact that friend should make their moves one be one and the friend who initially was left should move to the right and other friend should move to the left. Let len = |a - b|. Then the first friend will make cntA = len / 2 moves, and the second friend — cntB = len - len / 2 moves. So the answer is the sum of two arithmetic progressions cntA·(cntA + 1) / 2 and cntB·(cntB + 1) / 2.

The given constrains allowed to calculate this sums in linear time — simply iterate from 1 to cntA for the first sum and from 1 to cntB to the second.

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Thanks GreenGrape for translation!

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By KAN, 7 months ago, translation, In English,

Hello everybody!

Today, on March 4th 2018 the final round of Technocup olympiad for Russian-speaking high school students is held. The round starts at 11:30 Moscow time.

After the round starts, you can watch the current results.

For those who want to compete on the same problems, we will host two Codeforces rounds: one for the first, and one for the second division. The rounds will start at 15:35 UTC, don't miss them!

If you compete in the Final Round today, you can't compete in the rounds at evening.

The problems are prepared by Endagorion, komendart, syncopate, AndreySergunin, fcspartakm, MikeMirzayanov and me. For testing the problems many thanks to demon1999, Belonogov, gritukan, adedalic, BudAlNik, GreenGrape, Ne0n25! Also many thanks to gritukan for his help in hosting the round at Codeforces!

P.S. Because of the olympiad, some Codeforces features may be disabled today.

Good luck!

UPD: Congratulations to Technocup winners!

  1. qoo2p5
  2. dima_z
  3. 300iq

Congratulations to winners of Codeforces rounds!

First division:

  1. V--o_o--V
  2. Petr
  3. Merkurev
  4. Benq
  5. dotorya

Second division:

  1. Deanamic_Programming
  2. kiber
  3. shad0w_walker
  4. Vitalya
  5. leedsjays

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By KAN, 8 months ago, translation, In English,

I'm sorry for the delay, it took some time for me to translate analysis to English.

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Problem author: KAN, preparation: KAN.

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Problem author: KAP, preparation: KAP.

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Problem author: KAP, preparation: demon1999.

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Problem author: ZhNV, preparation: ZhNV.

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Problem author: SYury, preparation: kuzmichev_dima.

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Problem author: KAP, preparation: KAN.

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By KAN, 8 months ago, translation, In English,

Hi!

The Codeforces Round #464 (Div. 2) is going to be held on Saturday, 17 February 2018 at 10:05 UTC for participants from division 2.

The round is based on XIV Nizhny Novgorod Olympiad in Informatics named after V. D. Lelyukh for high school students, which will take place on Saturday in Nizhny Novgorod. However, the problems for the Olympiad and for the round are not completely identical.

The problems were prepared by KAP, ashmelev, ZhNV, kuzmichev_dima, demon1999, SYury, mmatrosov and me. Thanks to mike_live and vepifanov for testing the problems, and gritukan and MikeMirzayanov for helping us to host the round on Codeforces!

As usual, participants from division 1 can take part out of competition.

Good luck and have fun!

UPD: There will be 6 problems with the following scores: 500-1000-1500-2000-2500-2750.

You will be able to view submissions and tests after the end of the olympiad in Nizhny Novgorod around 13:30 UTC.

Congratulations to winners!

Div. 2:

  1. LitiIsPretty
  2. newbiedmy
  3. lijian666
  4. S.H.I.E.L.D
  5. OYZYWIN

Div. 1:

  1. dotorya
  2. eddy1021
  3. DmitryGrigorev
  4. uwi
  5. georgerapeanu

The editorial is here.

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By KAN, 11 months ago, translation, In English,

Hi all!

This weekend, at 16:05 UTC on November 12th, 2017 we will hold Codeforces Round 445. It is based on problems of Technocup 2018 Elimination Round 3 that will be held at the same time.

Technocup is a major olympiad for Russian-speaking high-school students, so if you fall into this category, please register at Technocup 2018 website and take part in the Elimination Round.

I want to thank MrKaStep, komendart, veschii_nevstrui, bixind, AndreySergunin and DPR-pavlin, who authored and prepared problems for Technocup, and lewin, who kindly suggested the last problem. I also want to thank zemen and AlexFetisov for testing the round.

Div. 1 and Div.2 editions are open and rated for everyone. Register and enjoy the contests!

UPD: We apologize that we run into technical issues during the round. The round will be unrated. I hope you liked the problems.

Anyway, congratulations to winners!

Технокубок 2018 - Отборочный Раунд 3

  1. potapov_al
  2. gainullin.ildar
  3. qoo2p5
  4. Vosatorp
  5. manoprenko

Codeforces Round #445 (Div. 1, based on Technocup 2018 Elimination Round 3)

  1. V--o_o--V
  2. Petr
  3. Um_nik
  4. SirShokoladina
  5. LHiC

Codeforces Round #445 (Div. 2, based on Technocup 2018 Elimination Round 3)

  1. mosthenio
  2. Ingugugus
  3. paulsohn
  4. xX_ucfNOTpt_Xx
  5. OmarYasser

Editorial is published.

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By KAN, 15 months ago, translation, In English,
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Thanks Arpa for this editorial!

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Thanks Arpa for this editorial!

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By KAN, 15 months ago, translation, In English,

The analysis is being updated.

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Thanks Arpa for the proofs!

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By KAN, 15 months ago, translation, In English,

Hi!

On Thursday, July 13, 2017, at 15:05 UTC Codeforces Round #424 will be held. Some of the problems will be from VK Cup 2017 Finals, some are prepared by Codeforces team to complete the problemset.

There will be six problems in the second division, five as usual in the first, three of them shared. The problems of this round are proposed, prepared and tested by: send_nodes, akvasha, ilya_the_lamer, fcspartakm, Perforator, MikeMirzayanov, PavelKunyavskiy, qwerty787788, Belonogov, izban, tourist, vepifanov, AlexFetisov, winger, Errichto, Gassa, naagi, ashmelev, Endagorion, ifsmirnov, Arterm and me. Huge thanks to all who helped with the preparation!

There will be prizes from VK social network in this round as well! Namely, among participants solved five or more problems in second division, or two or more problems in first division, five are to be selected randomly. They will receive championship souvenirs. There is no country nor language restriction, everyone can win a prize. One don't have to have participated in VK Cup to receive the prize. Exact selection algorithm will be announced before the start of the round.

Good luck!

Congratulations to the winners!

Div. 1:

  1. TakanashiRikka
  2. moejy0viiiiiv
  3. Petr
  4. anta
  5. matthew99

Div. 2:

  1. ccz181078
  2. repeating
  3. ioyeoa
  4. ReaLNero
  5. beet

The analysis is here.

The problems correspond to problems of VK Cup 2017 - Finals as follows:

Congratulations to souvenir winners!

Eligible list place Contest Rank Handle
65 830 65 halin.george
69 830 69 Neil
153 830 153 BigBag
265 830 266 whczr
320 830 323 Rydberg

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By KAN, 15 months ago, translation, In English,

Hi!

On Tuesday, July 11, 2017, at 16:35 UTC Codeforces Round #423 will be held. Some of the problems will be from VK Cup 2017 Finals, some are prepared by Codeforces team to complete the problemset.

Note that there will be two rounds based on VK Cup Finals, so I want to ask finalists not to discuss problems until the end of the second round.

There will be six problems in each division, four of them shared. The problems of this round are proposed, prepared and tested by: gritukan, demon1999, fcspartakm, Perforator, MikeMirzayanov, PavelKunyavskiy, qwerty787788, Belonogov, izban, tourist, vepifanov, AlexFetisov, winger, Errichto, Gassa, naagi, ashmelev, Endagorion, ifsmirnov, Arterm and me. Huge thanks to all who helped with the preparation!

There will be prizes from VK social network in this round! Namely, among participants solved five or more problems in second division, or three or more problems in first division, five are to be selected randomly. They will receive championship souvenirs. There is no country nor language restriction, everyone can win a prize. One don't have to have participated in VK Cup to receive the prize. Exact selection algorithm will be announced before the start of the round. There will be prizes in the second round using Finals' problems as well!

Good luck!

Congratulations to the winners!

Div. 1:

  1. W4yneb0t
  2. moejy0viiiiiv
  3. koosaga
  4. Radewoosh
  5. dotorya

Div. 2:

  1. ccz181078
  2. rqy1458814497
  3. houruize
  4. _Is_It_Rated_
  5. liutianyi000

The analysis is here.

Corresponding problems from VK Cup 2017 - Finals:

The souvenirs winners are:

Eligible list place Contest Rank Handle
19 827 19 zeliboba
42 827 42 kevinsogo
114 827 115 triploblastic
125 827 126 lexuanan
138 827 140 alex256

Congratulations!

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By KAN, 15 months ago, translation, In English,

Today, on July 9, 2017 the VK Cup 2017 Finals is being hold in Saint Petersburg!

Just to remind you, the total prize fund is 2490368 rubles, 20 teams consisting of 39 contestants in total will fight for it. Past years champions are tourist and niyaznigmatul in 2015, and tourist and subscriber in 2016. Who is going to take the first place today?

You can watch live results of the competition here, the start is at 08:05 UTC.

Good luck to all contestants and fans!

Final standings

UPD: Hooray! The results of the final competition were summed up. Congratulations to the winners!

  1. ershov.stanislav, aid,
  2. V--o_o--V, LHiC,
  3. enot110, I_love_Tanya_Romanova,
  4. zemen, Zlobober,
  5. nikgaevoy, gnomina007,
  6. RomaWhite, witua,
  7. Trumen, felix,
  8. Rubanenko, MrDindows,
  9. Tima, AKim,
  10. Golovanov399, I_hate_ACM,
  11. Goofy57, Shapo,
  12. ztk, ballon,
  13. Nobik_Glem, Omelianenko,
  14. Seemann, george..s,
  15. Temirulan, aidos.nurmash.
  16. EvErka, greencis,
  17. IlyaLos, extraVirgin20,
  18. YakutovDmitriy, BudAlNik,
  19. Lilith, Copymaster,
  20. SergeiFedorov.


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By KAN, 15 months ago, In Russian,

Ура! В эти выходные, 8-9 июля, в Санкт-Петербурге в главном офисе компании ВКонтакте состоится финал VK Cup 2017!

Лучшие 20 команд по результатам отбора будут соревноваться за звание Чемпиона и солидные денежные призы:

  • 1 место — 1048576 рублей
  • 2 местo — 524288 рублей
  • 3 местo — 262144 рубля
  • 4-8 места — 131072 рубля

В этом году финалистами стали:

  1. zemen (Константин Семенов, Москва), Zlobober (Максим Ахмедов, Москва),
  2. V--o_o--V (Владислав Макеев, Москва), LHiC (Михаил Ипатов, Москва),
  3. RomaWhite (Роман Білий, Львов), witua (Віталій Герасимів, Львов),
  4. YakutovDmitriy (Дмитрий Якутов, Пермь), BudAlNik (Николай Будин, Киров),
  5. Golovanov399 (Александр Голованов, Казань), I_hate_ACM (Никита Уваров, Москва),
  6. Lilith (Анастасия Софронова, Санкт-Петербург), Copymaster (Алексей Гордеев, Санкт-Петербург),
  7. ershov.stanislav (Станислав Ершов, Санкт-Петербург), aid (Айдар Сайранов, Санкт-Петербург),
  8. Tima (Темірлан Сатылханов, Талдыкорган), AKim (Андрей Ким, Талдыкорган),
  9. Nobik_Glem (Владислав Глембоцький, Хмельницкий), Omelianenko (Андрій Омельяненко, Кременчуг),
  10. enot110 (Владимир Смыкалов, Санкт-Петербург), I_love_Tanya_Romanova (Богдан Прищенко, Львов),
  11. Trumen (Тарас Савіцький, Львов), felix (Володимир Радюк, Львов),
  12. SergeiFedorov (Сергей Федоров, Москва) — команда из одного человека!,
  13. IlyaLos (Илья Лось, Саратов), extraVirgin20 (Данил Сагунов, Астрахань),
  14. nikgaevoy (Никита Гаевой, Санкт-Петербург), gnomina007 (Иван Бочков, Ижевск),
  15. Rubanenko (Роман Рубаненко, Кременчуг), MrDindows (Евгений Задорожний, Запорожье),
  16. Seemann (Кирилл Симонов, Санкт-Петербург), george..s (Георгий Струков, Санкт-Петербург),
  17. Goofy57 (Сергей Волнов, Москва), Shapo (Никита Шаповалов, Подольск),
  18. EvErka (Валентин Витязь, Минск), greencis (Иван Лукьянов, Минск),
  19. ztk (Артём Зинченко, Киев), ballon (Іван Здомський, Киев),
  20. Temirulan (Темирулан Мусаев, Алматы), aidos.nurmash (Айдос Нұрмаш, Кызылорда).

Традиционно, за день до Финала пройдет неофициальное соревнование CodeGame Challenge. После четырех часов напряженного контеста все смогут на большом экране наблюдать за тем, кто станет победителем, и, конечно, болеть за свои стратегии!

Зрители смогут наблюдать за соревнованиями по ссылкам, которые добавим чуть позже. А задачи финала можно будет порешать всем желающим в виде раунда Codeforces, который состоится совсем скоро после финала.

Желаю удачи участникам и побольше позитива на туре!

UPD: Результаты пробного тура уже можно наблюдать по ссылке!

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By KAN, history, 16 months ago, translation, In English,

During the discussion after the Round 421 it turned out that the author's solution was wrong. Yes, we had several testers, we had a bruteforce solution that worked correctly, we had a stress testing between the bruteforce and the main solutions. However, all these measures haven't prevented the mistake: the testers haven't noted the issue, the stress haven't found any counter-tests. The solutions also produced the same answers all small tests we had in the testset, so we only found the issue when a test used for a hack was added.

We are terribly sorry about the mistake. We did our best to ensure the problems are ok, I don't know any available method that we haven't used to check the problem.

We've spent the last few hours trying to come up with a new, correct solution to the problem, but right now I don't see any solution that seems undoubtedly correct to me. There are a few that work better than the author's, but yet unproved, you can try to prove this one, for example. I think this problem should be solvable with careful case analysis, and I'm trying to do this right now. I'll post the results here. I'd also be glad if someone post the solution with proof.

Thus, I apologize that the round should be declared unrated. Hope for your understanding.

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By KAN, 17 months ago, translation, In English,
A: Carrot Cakes
B: T-shirt buying
C: Fountains
D: Field expansion
E: Aquarium decoration
F: Beautiful fountains rows
G: Cut the pie

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By KAN, history, 18 months ago, In Russian,

Хочу сказать огромное спасибо fcspartakm, который подготовил задачи и разборы!

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By KAN, 18 months ago, translation, In English,

Hi all!

Tomorrow, on April 5th 2017, at 15:35 UTC the first Wild-card Round of VK Cup 2017 will be held. Along with it there will be parallel unofficial round in which everyone can take part.

The rounds will use special rules, the rounds will be unrated. The problems were prepared by Codeforces team.

The detailed rules will be added to this post 30 minutes before the rounds. I can say now that there will be 24-hours open hacks phase after the round, like in Codeforces Educational Rounds.

Round rules:

The round will be almost usual contest with ACM ICPC rules. There will be 12 problems for 2 hours. During the round your solutions will be tested on some basic tests, they should be much stronger than usual pretests. After the round you will have 24 hours to find tests against other participants’ solutions, this part is the same as in Educational rounds. After that we will add all succesful hacks and our tests and rejudge all submissions. Then the results will be final.

The main difference between ACM ICPC rules and this round is the following rule.

You should submit each problem in a unique programming language. Different compilers of same language are considered the same language. For example, GNU G++, GNU G++ 11, GNU G++ 14 and MS C++ compilers are C++ language. Thus, you are not only to solve problems, but also try different and new for you languages. We don’t think you know 12 languages, we hope that you will quickly learn some basic syntax.

Formally, the following check is performed when you submit a task:

  • If there is at least one submission in queue or submission that passed at least one test for this problem in another language, your solution will be ignored. Thus, if your program passes at least one test, you can only solve this problem using this language.
  • If there is at least one submission in queue or submission that passed at least one test for another problem in same language, your solution will be ignored. Thus, you can’t use a language for more than one problem.

Remember that you can view filter status of some other round by language and view submissions in a specific language. Also, you can view examples of codes in any of the supported languages on the table below. Also, the table contains the groups of compilers considered the same language.

You can use “custom invocation” tab to run a solution if you don’t have the compiler locally.

Language Group Compilers Examples
C GNU C, GNU C11 10903473, 17029870
C++ GNU C+, GNU C++11, GNU C++14, MS C++ 23794425, 5456501
C# Mono C#, MS C# 3195513, 3794163
D D 5482410, 2060057
Go Go 7114082, 21366098
Haskell Haskell 455333, 1668418
Java Java 8 25491359, 23678167
JavaScript V8 6174887, 5743720
Kotlin Kotlin 25779271, 25204556
OCaml OCaml 6157159, 1281252
Pascal Delphi, FPC 1275798, 1259434
Perl Perl 2519448, 1277556
PHP PHP 413942, 4475965
Python Python 2, Python 3 4432133 (Py2), 15729882 (Py3)
Ruby Ruby 1837970, 1289551
Rust Rust 25180002, 24643411
Scala Scala 22577830, 2456025

The main rules of ACM ICPC contest: each problem can either be completely solved (when all tests are passed), or not solved. The participants are ranked by the number of solved problems, in decreasing order, in case of a tie they are ranked by penalty time. The penalty time is the sum among all problems the time in minutes that had passed between the start of the round and the moment the problem got solved, plus 20 minutes for every rejected submission. Note that the problems are not arranged by difficulty. Also, you can resubmit a solution even if it passed all tests, because there will be more tests after the open hacks.

Good luck!

Open hacks phase has ended, the solutions are rejudged. Congratulations to winners!

Official round:

  1. I_love_2007, Ed_Os
  2. VernitaGreen, svxf
  3. gars, Provet
  4. Me-and-Myself, zetilovn
  5. svetlana_lana, GoldenMan

Open mirror:

  1. lewin
  2. Bugman
  3. uwi
  4. ifsmirnov
  5. Tinsane

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By KAN, 19 months ago, translation, In English,

Hello everybody!

The Technocup 2017 (a competition for high-school students hosted by Mail.Ru Group together with MIPT, Bauman MSTU and Codeforces) Finals is happening tomorrow in Moscow. For those who will not participate in the Finals, we prepared mirror contests for both divisions. The round will start at 13:05 UTC at Sunday, March 5th, 2017 and will last for two hours.

The round was prepared by Endagorion, WHITE2302, Alladdin, fcspartakm, Amethyst1, MikeMirzayanov, ifsmirnov and me.

You can view the current onsite results at link.

There will be six problems in each division.

Editorial is here.

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By KAN, 20 months ago, translation, In English,
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