By manvscode, history, 4 days ago, In English,

Hello CodeForces Community!

I’d like to invite you to participate in CodeChef’s global annual onsite programming contest SnackDown 2017 Qualifier which starts day after tomorrow i.e. 20th May, 2017. This time there are no restrictions on team formation (except max size of two). So, that leaves us with no reason to not take part in the contest. I am certain you will enjoy not only the exciting finale setup but also the brilliant problems.


You can register in a team of two or can go solo into the contest. The Online Qualifier starts at 20th May,2017.

If you are yet to register, you can do so here:


Along with the cash prizes for Global Winners, there are special prizes for Best School Team, Best Girls team and Best Indian Team (the total cash prizes are worth $20,500). The winning team shall win a whooping cash prize of $10,000. Top 300 Teams In the Elimination Round will get a cool SnackDown t-shirt. Every team member of the qualifying teams for the elimination round will get a domain name from Radix registry. Certificate of Participation-All the teams advancing from the Qualifiers to further rounds will receive a digital certificate of Participation from CodeChef.

Previous Years:

Last years star-studded final was won by pattern_avoid team (Gennady Korotkevich and Borys Minaiev).

Sponsorship for onsite round:

Travel expenses of the top 25 teams: Top 15 teams will be entitled for an all expense paid trip to Mumbai. The top 15 Indian teams that arrive at the finale will be entitled for an all expense paid trip to Mumbai. (Provided that they do qualify for the onsite finale. The top 10 teams are guaranteed an entry. The next 5 Indian teams have to be in top 100 of the Elimination round to be eligible for onsite finale. See rule 4 above under Onsite Finale).

For more elaborate rules click here.

Also, taking into consideration the previous discussions regarding the timing of online elimination round of the contest, the organizers had done a poll beforehand, so as to satisfy time demands by more contestants.

I hope you like the new timings and that will enjoy the contest till the very end. That will be all from my side for now. See you all at the contest. Regards, Ciao, Siba Prasad Tripathy (manvscode)

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By hloya_ygrt, history, 6 days ago, translation, In English,

Hello everyone!

This Saturday May 20, 21:05 MSK rated Codeforces Round #415 takes place.

As for our previous round 384, the problems were set by Kiril kefaa Gulin and Yura hloya_ygrt Shilyaev. And this time Daniil Melnik Melnichenko joined us! Many thanks to coordinator Alex netman Vistyazh for help in preparations of the round, and also to Mike MikeMirzayanov Mirzayanov for Codeforces and Polygon systems.

While everyone is waiting for second half of "SKAM" series season, we offer you to solve problems, main characters of which would be stunning girl Noora and well-known to you from 794F - Leha and security system hacker Leha!

As always, participants of both divisions will be given 5 problems and 2 hours to solve them. Scoring will be announced before the round.

We hope you'll like our round! I wish everyone good luck and high rating!

UPD: Please pay attention that round was rescheduled.

UPD2: Scoring in each division is standart 500 — 1000 — 1500 — 2000 — 2500

UPD3: We are extremely sorry about the issue with problem C, but since it affected not many participants, round remains rated. At the same time, we can remove your unnecessary submissions and if you were affected, we can make round unrated for you. Please contact KAN with this question.

UPD4: Congratulations to the winners! Editorial will be posted tomorrow.


  1. Radewoosh

  2. izrak

  3. mnbvmar

  4. ershov.stanislav

  5. V--o_o--V

  6. Um_nik

  7. Arterm


  1. polygonia

  2. Delsin

  3. utsav.delhi2

  4. Cypi

  5. altruist

  6. Anachor

  7. shadowatyy

UPD5: Editorial is available

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By BledDest, 8 days ago, translation, In English,

Hello Codeforces!

On May 15, 18:05 MSK will be held Educational Codeforces Round 21.

Series of Educational Rounds continue being held as Harbour.Space university initiative! You can read the details about the cooperation between Harbour.Space and Codeforces in the blog post.

The round will be unrated for all users and will be held on extented ACM ICPC rules. After the end of the contest you will have one day to hack any solution you want. You will have access to copy any solution and test it locally.

You will be given 7 problems and 2 hours 30 minutes to solve them. We hope that everyone will find something interesting in this contest.

The round was prepared by Mikhail PikMike Piklyaev, Mikhail MikeMirzayanov Mirzayanov and me.

Here is message from Igor Maksimov, Harbour.Space University.

I want to make an announcement of the upcoming 2nd Hello Barcelona ACM-ICPC Bootcamp that will take place in Barcelona from the 27th of September until the 4th of October 2017, in collaboration with Moscow Workshops ACM ICPC, is an opportunity for teams of different levels to prepare for successful participation in ACM ICPC.

The Bootcamp will be split in two divisions:

  • Division A. Designed to prepare students to excel and win medals in the next ACM-ICPC World Finals.
  • Division B. Division B. Designed to help teams prepare for the next season of ACM ICPC Regionals and international competitions. This is an appropriate introduction for teams and students new to the world of ACM ICPC and competitive programming competitions in general. The Division B curriculum features thematic lectures and contests. University introduce the video about the 1st ACM-ICPC Programming Bootcamp held in February, 2017.

Take a part of the upcoming 2nd Hello Barcelona ACM-ICPC Bootcamp that will take place in Barcelona from the 27th of September until the 5th of October 2017.

More information →

Good luck to everyone!

UPD: Editorial is out.

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By RussianCodeCup, history, 9 days ago, translation, In English,

Ready, steady, go!

It's time to find out who the top 50 participants to compete in the Final Round of Russian Code Cup 2017 are. We invite everyone qualified to take part in the Elimination Round this Sunday, May 14, 2017 at 13-00 Moscow Time. Round length is 2 hours. We invite you to, and wish you good luck!

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By GlebsHP, history, 9 days ago, translation, In English,

Hello everybody!

Tomorrow, at 10:00 Moscow time will be held Round 1 of Yandex.Algorithm competition, authored by me. I would like to thank Zlobober for all the job he does to make this competition interesting, MikeMirzayanov for the great polygon that ease the preparation process a lot, and everyone, who tested the round and made useful comments. Of course, we did our best to make the problem diverse by topics and difficulty.

See you in the competition dashboard!

UPD Thanks to everyone who participated, hope each of you found at least one interesting problem. We apologize for the situation with problem F, we have googled for all the problems and asked all testers whether they have seen such problems or not, but that didn't helped. The editorial has been published.

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By zscoder, 11 days ago, In English,

Hi all!

On May 13, 12:35 MSK, Tinkoff Challenge — Final Round will be held. Standings of the official finalists are availiable here.

The authors of the round are me (zscoder, Zi Song Yeoh), AnonymousBunny (Sreejato Kishor Bhattacharya), hloya_ygrt (Yury Shilyaev).

Special thanks to KAN (Nikolay Kalinin) for coordinating the round, winger (Vladislav Isenbaev) and AlexFetisov (Alex Fetisov) for testing the problems. Also, thanks to MikeMirzayanov (Mike Mirzayanov) for the Codeforces and Polygon system.

There are seven problems and the duration is two hours. Scoring will be announced before the round.

Top 20 participants of the Elimination Round will compete in the Tinkoff Office.

The round is rated. Division 1 and Division 2 will have the same problemset with seven problems.

We hope everyone will find interesting problems and get high rating!

UPD : Scoring Distribution : 500 — 1000 — 1750 — 2000 — 2500 — 2750 — 3500

UPD2 : The editorial is out!

UPD3 : Congratulations to the top 10 :

  1. V--o_o--V

  2. LHiC

  3. Um_nik

  4. Petr

  5. Shik

  6. TakanashiRikka

  7. Seter

  8. SirShokoladina

  9. matthew99

  10. DBradac

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By MikeMirzayanov, 12 days ago, translation, In English,

Hello, Codeforces!

I'd like to invite you to join in Playrix Codescapes Cup for the both divisions that will be held on May 11 at 18:35 MSK. The round is rated and open for everyone.

Problems are prepared by KAN, Al.Cash, MikeMirzayanov and fcspartakm. Huge thanks to Playrix company for making this round possible. Hope you enjoy the round!

Playrix is one of the leading mobile games development companies in the world. Its distributed team consists of 450 professionals from around the world. The company has released three successful mobile free-to-play games – Township, Fishdom and Gardenscapes. All of the projects have consistently been among the Top 50 Grossing Apps for iOS and Google Play since their release.In 2016, Facebook named Gardenscapes game of the year.

Company is looking for Russian-speaking C++ developers.

Prizes from the Playrix company:

  • Top 1: iPadPro 9,7 + PowerBank + T-shirt with logo
  • Top 2-5: PowerBank + T-shirt with logo
  • Top 6-50: T-shirt with logo
  • (New!) Random 5 participants (not from top-50, submitted at least once): T-shirt with logo

Congratulations to the winners!

  1. tourist
  2. LHiC
  3. subscriber
  4. W4yneb0t
  5. enot110

The problem analysis is published.

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By tourist, 2 weeks ago, translation, In English,

Hi everyone!

The last elimination round of VK Cup 2017, Round 3, will take place on May 7 at 18:35 MSK (check your timezone here), along with separate Codeforces Round #412 for both divisions. All three rounds will be three hours long, and all three rounds will be rated.

The contest "VK Cup 2017 — Round 3" is for teams qualified from Round 2 or Wildcard Round 2. The top 20 teams will advance to the final which will be held in July 2017 in Saint Petersburg!

Huge thanks to KAN, qwerty787788, PavelKunyavskiy, AlexFetisov, MikeMirzayanov, and VK company for making this round possible.

Codeforces will be the main character of most problems. Don't forget that it's useful to read the statements of all the problems.

Good luck!

As we're in year 2017, the scoring will obviously be static. The exact scoring distribution will be announced before the round.

UPD 1. The scoring distribution is:

Div. 1 and VK Cup Round 3: 500 — 1000 — 1750 — 2500 — 2750 — 3500

Div. 2: 500 — 1000 — 1500 — 2000 — 2750 — 3500

UPD 2. Due to yesterday's registration troubles the start of the contest is delayed by 10 minutes.

UPD 3. Congratulations to the winners!

VK Cup Round 3:

  1. zemen, Zlobober
  2. V--o_o--V, LHiC
  3. RomaWhite, witua
  4. YakutovDmitry, BudAlNik
  5. Golovanov399, I_hate_ACM

Div. 1:

  1. Petr
  2. yosupo
  3. rng_58
  4. uwi
  5. Nezzar

Div. 2:

  1. ltaravilse
  2. btk15049
  3. RCG
  4. SUSTechDFS
  5. hieutrungle

UPD 4. Tutorial is now available.

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By Sa1378, history, 3 weeks ago, In English,


I'd like to invite you to join in Codeforces Round #411 that will be held on May 4 at 17:35 MSK.

Actually I didn't do anything for this contest :) and most of the contest is prepared by my good friends ChamrAn and MohammadJA. Also Hifdah, Navick, Folorn, kastarika and I helped them in testing problems, writing statements and these sort of things. At the end, Thanks to KAN for his huge help in all of the contests and MikeMirzayanov for great Codeforces and Polygon platforms. (Sorry if there's someone I didn't mentioned, This is everything I know).

Each division contains 6 problems (4 common problems). Hope you enjoy them.

The round is rated and score distribution will be posted soon and good luck and have fun and hope you high ratings and all the other words that should be told.

UPD 1 Contest delayed by 10 minutes.

UPD 2 Contest delayed by 5 minutes. :)

UPD 3 We can see the scores now in contest page.

UPD 4 Contest is finally over, Hope you enjoyed the problems. Cause of technical issues editorial will be posted tomorrow.

UPD 5 And here are the top5 in each division:













And also congratulation to hahaschool, MKyzy and shanin who solved problem F in div2.

UPD 6 Editorial is ready now.

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