By mahmoudbadawy, history, 7 weeks ago, In English,

Hello Codeforces!

I'm glad to announce that on Feb/07/2017 17:05 UTC Codeforces Round #396 for the second division will take place. As usual, First division participants can take part out of competition.

This round was prepared by me and mohammedehab2002.

I'd like to thank moaz123 for helping us prepare the round, zoooma13 for testing some problems, KAN for helping us in contest preparation and for translating the statements into Russian and MikeMirzayanov for the great Codeforces and Polygon platforms.

You will be given 5 problems and 2 hours to solve them.

The scoring distribution will be announced later.

UPD 500-1000-1500-2000-2500

UPD editorial is ready

UPD Congratulations to the winners!


  1. Verstand

  2. sd0061

  3. rajat1603

  4. gritukan

  5. ulna


  1. Verstand

  2. zhfs_ga_pitona

  3. zelta

  4. AomeII

  5. bciobanu

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By platypus179, history, 2 months ago, translation, In English,

Ladies and gentlemen!

Codeforces Round #395 for both divisions will happen tomorrow, on Thursday, 2 February 2017 at 13:35 UTC.

Problems were prepared by me (Vasiliy Alferov) and students of Moscow school #179: s17b2_voroneckij (Dima Voronetsky), ilya_the_lamer (Ilya Pauzner) and akvasha (Anton Kvasha). Also, KAN (Nikolay Kalinin) is author of one of the problems.

Invaluable help was given to us by Codeforces coordinator KAN (Nikolay Kalinin). Thanks to MikeMirzayanov (Mike Mirzayanov) for wonderful platforms Codeforces and Polygon. Also thanks to Endagorion (Mikhail Tikhomirov), winger (Vladislav Isenbaev), AlexFetisov (Alex Fetisov) and cdkrot (Dmitry Sayutin) for reading out our statements and testing the round.

Participants will be given five problems in both divisions. Some of the problems will be common for both divisions. The scoring distribution will be announced later.

Good luck to all!

UPD: Scoring distribution:

Div1: 500-750-1500-2000-2500

Div2: 500-1000-1500-1750-2500

UPD2: The contest is over. Hope you enjoyed the problems :)

UPD3: Congratulations to the winners!

Div 1:

  1. moejy0viiiiiv

  2. V--o_o--V

  3. fjzzq2002

  4. SkyDec

  5. uwi

  6. Belonogov

  7. aid

  8. dreamoon

  9. Um_nik

  10. Andrei1998

and Div 2:

  1. ljh2000

  2. MashiroSky

  3. sqcszboyi

  4. _Reborn_

  5. Factorio

  6. Dirak

  7. lnjlnj

  8. Manchery

  9. SarvagyaAgarwal

  10. mik

The editorial will be posted very soon.

UPD5: Editorial

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By Vladik, 2 months ago, translation, In English,

Hi there!

Codeforces round #394 for the second division will take place at the time of Tuesday, 31 January 17:35 MSK. Participants from the first division can compete out of competition. Contestants will have 2 hours and 6 problems to solve.

  • Problems were developed by me (Vladislav Vishnevki) and Denis Anischenko (altruist).
  • Alexey Vistyazh (netman) helped us as a contest coordinator.
  • Aliaksandr Drapko (sdryapko) and Alena Yaros were reading the statements carefully.
  • Vlad Khala (hapooo) tested the round.
  • Olya Yakovchik drew amazing illustrations for the problems.
  • Yuri Shilyaev (hloya_ygrt) translated editorials and round announcement for you.
  • And of course the round couldn't happen without (MikeMirzayanov), the author of platform polygon and codeforces, and also author of the idea to one of our problems.

Thanks everyone listed for the contribution you made to the contest preparation!

The main character of the legends is tiger Dasha, which loves to solve puzzles and make origami figures.

Good luck everyone! :)

UPD Round will consist of 6 problems.

UPD 500-1000-1500-2000-2500-3000

UPD Contest finished. It was decided to make round unrated, because codeforces is unstable now. I am really sad about that :( I hope everyone found a problem he liked. Editorial will be posted soon.

UPD Top 10 participants from second division: 1. mitterr
2. wh2000
3. Inhibitor
4. Border_Collie
5. HanwhaEagles
6. Vergara
7. zelta
8. GGOSinon
9. X-tazy
10. tonykky

Top 10 participants from first division: 1. eddy1021
2. Myungwoo
3. dreamoon
4. natsugiri
5. Shik

Congratulations to the winners!

UPD Editorial.

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By HellKitsune, history, 2 months ago, translation, In English,


After a long break, on Jan 25, 17:35 MSK will be held Educational Codeforces Round 17.

You will be given 6 tasks and 2 hours to solve them. The problemset, in my opinion, turned out to be well balanced and should be interesting for both novices and experienced participants. Task F may end up beneficial for many reds :)

The ideas for problems are by MikeMirzayanov and me. Thanks to fcspartakm for helping in preparation of this round.

I hope you will enjoy the problems and good luck!

UPD: The contest is over. Probably a little bit on the hard side for the beginners? Sorry! Editorial will be in the form of hints and will appear shortly.

UPD2: Editorial

UPD3: Challenge phase is over! Congratulations to winners:

  1. eddy1021
  2. W4yneb0t
  3. kmjp
  4. LHiC
  5. Narenji58

Also, top hackers!

  1. halyavin +249 : -35
  2. step_by_step +82 : -11
  3. -Morass- +51 : -141
  4. MishaPrigara +50 : -5
  5. uwi +46 : -9

If you want to share your ideas about tasks for next Educational Rounds, you can use the new problem proposal form. Please, use prefix "er-" in the name of the task so that we know that it is for Educational Rounds.

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By KAN, 2 months ago, In English,

Hi all,

The 8VC Venture Cup 2017 - Final Round is tommorrow at 18:05 UTC. Along with that, Codeforces Round #393 will be held at the same time both for Div. 1 and Div. 2 participants. The Div. 1 Edition will contain the same problems as the Final Round, the Div. 2 Edition will be easier.

Of course, those who have placed in top 200 in 8VC Venture Cup 2017 - Elimination Round should register for the Final Round, all the others should register for Div. 1 or Div. 2 editions according to their rating. All three contests will contain six problems, last two hours and be rated.

The problem authors are Um_nik, Endagorion, Umqra, pashka and me. Also huge thanks to fcspartakm for his help in preparation, and to vepifanov and AlexFetisov for testing the round. I suggest you reading all the problems to find which one you like the most!

I'd like to remind you about the prizes:

  • Overall 1st place — $2000
  • Overall 2nd place — $1000
  • Overall 3rd-5th places — $500 each
  • Overall 1-50th place — t-shirts with 8VC and company logos
  • Local Winner — Dinner with Joe Lonsdale (founder of Palantir, Addepar and 8VC) and other Silicon Valley technologists
  • Local top finishers — Opportunity to meet with leadership from 8VC portfolio companies

Please welcome one more company became interested in the Venture Cup, Progressly!

Progressly is a cloud-based Operational Performance Management platform allows you to document, collaborate on, and gain contextual insights into core business processes and outcomes in real time.

The scoring is usual in all three contests: 500-1000-1500-2000-2500-3000.

Congratulations to the winners!

8VC Vecture Cup 2017 winners:

  1. V--o_o--V
  2. bmerry
  3. Marcin_smu
  4. LHiC
  5. qwerty787788

Codeforces Round #393 Div. 1 winners:

  1. cubelover
  2. RomaWhite
  3. PavelKunyavskiy
  4. snuke
  5. gritukan

Codeforces Round #393 Div. 2 winners:

  1. Kacey
  2. wcx5tq957i
  3. Bekzhan.Kassenov
  4. Tailz
  5. ETA-Mu


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By Kniaz, 2 months ago, translation, In English,

Hello everybody!

I am glad to announce that at 19 January 2017 18:05 MSK will take place Codeforces Round #392 for participants of Div.2. Participants from the Div.1 may participate out of the competition as usual.

You will be offered 6 problems and 2 hours for solving them.

Great thanks to Nikolay Kalinin (KAN) and Alexey Vistyazh (netman) for their help with the contest preparation, Tatiana Semenova (Tatiana_S) for translating the statements and Mike Mirzayanov (MikeMirzayanov) for the Codeforces and Polygon systems and also for help with ideas of some problems and their preparation.

It's my second round and I hope that you like it more than the previous one. Fair rating to everyone!

UPD: Scoring 500 — 1000 — 1500 — 1750 — 2500 — 3000.

UPD: Editorial!!! I want to thank Mikhail Piklyaev (PikMike) and Tatiana Semenova (Tatiana_S) for translation of tutorial!

Congrats to the winners!

Div. 2

I wolf29

II alexwice

III WhyamIhere

4 TaTaPiH

5 Life_chicken

6 RewriteHarvestFesta

7 D0zingBear

8 whzzt

9 _Lucas97

10 Clayton

Div. 1

I W4yneb0t

II sd0061

III irkstepanov

4 wolf29

5 I_love_Tanya_Romanova

6 HellKitsune

7 kraskevich

8 kmjp

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By Miyukine, 2 months ago, In English,

Hello everyone! The first round of the 8VC Venture Cup 2017 will be held on Sunday.

I am honoured to be the problemsetter of the round. Reyna helped me a lot. Huge applause to KAN for his valuable coordinator's help, and MikeMirzayanov for his admirable work for the Codeforces comunity. I also want to thank testers very much (Alexey ashmelev Shmelev and Alex AlexFetisov Fetisov).

This round is a first stage of 8VC Venture Cup 2017. If you want to acknowledge yourselves with the competition, try here.

The main character of the round is PolandBall. It's a small friendly Ball who lives in a forest along with other Balls. You'll surely like it :)

I tried to fulfill your demands with a various, interesting and challenging problems described in a concise way.

Hope to see you soon, good luck and have fun!

UPD1: Scoring 500100015002250250027503500.

UPD2 Thank you for participation! Contest is over. Did you like the problemset? Feel free to comment =)

UPD3 Editorial

UPD4: Winners

  1. tourist
  2. moejy0viiiiiv
  3. W4yneb0t
  4. ilyakor
  5. ainta.

Hope you've had a good time with PolandBall solving the problems.

Congratulations to all the winners and TOP-200 who advances into 8VC Finals =)

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By MikeMirzayanov, history, 3 months ago, In English,

Hello Codeforces!

I'm pleased to announce the first championship hosted on the Codeforces platform. Welcome 8VC Venture Cup 2017!

8VC will be hosting a coding championship on Codeforces. The championship will begin on January 15 and take place in 2 rounds.

The contest will occur in two rounds:

  • The Elimination Round is online and takes place on January 15, 17:05 (UTC). Elimination Round follows regular Codeforces rules and consists of 7-8 problems. For this round, the complexity of the problems will be comparable to a regular Codeforces round. There are no eligibility restrictions to participate in the round.
  • The Final Round takes place on January 22, consists of 5-6 problems, and uses regular Codeforces rules. The complexity of the problems is higher than a regular Codeforces round. We will invite the top local finishers in Elimination Round to Woodside, CA to compete in the Final Round. In addition, we will invite the top 200 overall finishers to compete online.

Cool prizes are offered to winners and best participants.

  • Overall 1st place — $2000
  • Overall 2nd place — $1000
  • Overall 3rd-5th places — $500 each
  • Overall 1-50th place — t-shirts with 8VC and company logos
  • Local Winner — Dinner with Joe Lonsdale (founder of Palantir, Addepar and 8VC) and other Silicon Valley technologists
  • Local top finishers — Opportunity to meet with leadership from 8VC portfolio companies

8VC, which consists of Joe Lonsdale (co-founder of Palantir) and his core team from Formation | 8, is a Silicon Valley venture capital firm that invests in industry-transforming technology companies. The team's investment portfolio includes companies such as the selected companies below, and a host of other top technology platforms that leverage modern algorithms and data science to power their core business processes.

Connect to 8VC

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By tanujkhattar, history, 3 months ago, In English,

Hello Everyone!

I would like to invite you to CodeCraft-17, which will take place on Thursday 12th January 2017, 9:05PM IST. The round will be a Div1 + Div2 combined round and is rated.

Felicity, IIIT Hyderabad presents Threads ‘17, the magnificent annual technical fest, is finally here in its 13th edition! With a plethora of intellectually engaging online contests in various fields of programming, mathematics and general knowledge, Threads is a celebration of the spirit of computing and engineering. The grand algorithmic sprint called CodeCraft, parallel programming in Kernel Cruise, mathematical enigmas in Gordian Knot, jeopardy style CTF event called Break In, overall Threads '17 has something to offer for every kind of computing enthusiast!

Codecraft Poster

I would like to thank Nikolay Kalinin (KAN) for helping us in preparing the contest,to Mike Mirzayanov (MikeMirzayanov) for the great Codeforces and Polygon platform and the Threads Team for helping in preparation of the problemset.


  • Top 25 participants win Codeforces T-shirts.
  • Additionally, 25 randomly chosen participants from top-500 will also win a Codeforces T-shirt.

You will be given seven problems and three hours to solve them. The scoring distribution will be announced later. Good luck everyone!

UPD: The constraint of registration for eligibility to prizes has been removed. Everyone who participates in the round is eligible for prizes. Sorry for the inconvenience caused!

UPD2: Scoring is 500 — 1000 — 1500 — 2000 — 2500 — 2750 — 3500

The contest has ended. Thank you all for participating. Hope you liked the problems.
It was our first codeforces round and it was really exciting for us to see how the contest progressed!
Editorials and list of T-shirt winners will be published soon.

Congratulations to the winners!

  1. tourist
  2. W4yneb0t
  3. anta
  4. Um_nik
  5. ershov.stanislav
  6. LHiC
  7. jcccccccccccccccccccccsb
  8. GlebsHP
  9. jiry_2
  10. Egor

UPD4: Editorial has been posted.

UPD5: The random t-shirts winners will be announced tomorrow according to the algorithm described in this comment.

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