By PikMike, history, 3 days ago, translation, In English,

Hello Codeforces!

On May/21/2018 17:45 (Moscow time) Educational Codeforces Round 44 will start.

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

This round will be rated for the participants with rating lower than 2100. It 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 to solve them.

The problems were prepared by Adilbek adedalic Dalabaev, Vladimir Vovuh Petrov and me.

Good luck to all participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Benq 6 143
2 crhkr 6 202
3 mjhun 6 210
4 nhho 6 210
5 krijgertje 6 223

Congratulations to the best hackers:

Rank Competitor Hack Count
1 step_by_step 248:-25
2 greencis 31:-6
3 zero-light-some 15
4 Necrozma 12
5 Codefocres 11:-1
703 successful hacks and 490 unsuccessful hacks were made in total!

And finally people who were the first to solve each problem:

Problem Competitor Penalty
A dotorya 0:01
B dotorya 0:03
C dotorya 0:10
D Benq 0:21
E SmsS4 0:07
F DarkestLight 0:49
G Marco_L_T 0:44

UPD: Editorial is uploaded

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By erdos, history, 5 days ago, In English,

Code Jam R2 starts in ~24h (Saturday, May 19th 14:00 UTC)

Let's discuss the problems after the contest!

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By AGrigorii, 7 days ago, translation, In English,

Hello, Codeforces!

I'd like to invite you to Codeforces Round #484 (Div. 2). It'll be held on May/17/2018 19:35 (Moscow time) and Div. 1 participants can join it out of competition. Please pay attention that round starts in the unusual time!

Me and Andrey API Pikas prepared the tasks for this round.

Great thanks to Nikolay KAN Kalinin for helping us preparing the contest, to Mikhail MikeMirzayanov Mirzayanov for the great Polygon platform and Codeforces and also to Kirill KittyLover Samelyuk, Nikolay Apollon76 Permyakov, Dmitry Krainov_Dmitry Krainov, Andrey GreenGrape Rayskiy and Alexey Um_nik Danilyuk for writing solutions.

You'll have to solve six tasks in two hours. The scoring distribution will be announced later

Good luck!

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

UPD2 Congratulations to the winners of the division 2:

  1. Kotori_Is_My_Wife

  2. vosptu

  3. ez_zkj

  4. relativity

  5. iordache.bogdan

And also our congratulations to the winners of both divisions:

  1. Claris

  2. Benq

  3. Kotori_Is_My_Wife

  4. kmjp

  5. vosptu

UPD3 The editorial will be published tomorrow.

UPD4 Editorial

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By Livace, 9 days ago, In English,

Hello, Codeforces!

Codeforces Round #483 will take place on May/15/2018 17:45 (Moscow time). The round will be rated for both divisions.

Problems were prepared by neckbosov, KAN and me.

Many thanks to testers qoo2p5, manoprenko, AlexFetisov, winger, cyand1317 and ashmelev.

Also thanks to MikeMirzayanov for Codeforces and Polygon and ifsmirnov for jngen.

Upd. The scoring distribution is 500-1000-1500-2000-2500 for div2 and 500-1000-1500- 2250 -2500 for div1.

Congratulations to the winners!


  1. fateice
  2. skuecrk
  3. Egor
  4. dotorya
  5. LHiC


  1. wevetriedly
  2. mraron
  3. adeliaut
  4. fengsuiyan
  5. K.F.Cat


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By htoj, 10 days ago, In English,

Hi Codeforces!

Sorry for being late for the announcement.

I'm glad to introduce to you my first contest Codeforces Round #482 (Div. 2). It will take place on 14.05.2018 17:35 (Московское время).

You will have 5 problems and 2 hours to solve them.

The problems were prepared by me (Quyen Dinh), _Kuroni_ (Trung Dang) and _Shirone_ (Lam Le) with suggestions from FallingStar1709 (Nhat Hoang) and HaiDang2001VN (Dang Huynh). I would like to thank KAN for his great help in checking the problems and giving comments, Tommyr7 for testing all the problems and MikeMirzayanov for the awesome Codeforces and Polygon platform.

Note that the round is rated for everyone with rating below 2100.

In this contest, you will meet Kuro, Shiro and Katie, the three naughty but smart cats who love asking thought-provoking questions. I hope you will find our problems interesting. Good luck to you all!

UPD: Also big thanks to cyand1317 for helping us with the problems and arsor for translating the problems into Russian. Sorry, I forgot you guys.

UPD2: The scoring distribution is 500 — 1000 — 1250 — 1750 — 2250. Have fun!

UPD3: Congratulations to the winners!

Div. 1 & Div. 2:

  1. dotorya

  2. mama_budra

  3. coach.31

  4. nuip

  5. kevinsogo

Our top 5 solved all the problems. Awesome!


  1. mama_budra (solved all problems!)

  2. coach.31 (solved all problems!)

  3. Illidan

  4. ranwen

  5. iloveUtaha

Thanks for everything! Here is the editorial.

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


Codeforces Round #481 (Div. 3) will start on May/13/2018 12:05 (Moscow time). It will be the second Div.3 round in the history of Codeforces. You will be offered 7 problems with expected difficulties to compose an interesting competition for participants with ratings up to 1600. Probably, participants from the first division will not be at all interested by this problems. And for 1600-1899 the problems will be too easy. However, all of you who wish to take part and have rating 1600 or higher, can register for the round unofficially.

The round will be hosted by rules of educational rounds (extended ACM-ICPC). Thus, during the round, solutions will be judged on preliminary tests, and after the round it will be a 12-hour phase of open hacks.

Remember that only the trusted participants of the third division will be included in the official standings table. As it is written by link, this is a compulsory measure for combating unsporting behavior. To qualify as a trusted participants of the third division, you must:

  • take part in at least two rated rounds (and solve at least one problem in each of them),
  • do not have a point of 1900 or higher in the rating.

Regardless of whether you are a trusted participant of the third division or not, if your rating is less than 1600, then the round will be rated for you.

The problem are written by me and fcspartakm. Many thanks to testers AGrigorii, BigBag, nhho and Sert!

Good luck!

UPD 1: Thank you for participation. Problem tutorials have been published.

UPD 2: Congratulations to the winners! Top-5 (official standings):

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By Harbour.Space, history, 13 days ago, In English,

Harbour.Space University, the International Tournament of Young Mathematicians (ITYM) and Moscow Institute of Physics and Technology (MIPT) are proud to announce a special high schooler's online test, May 26th at 15.00 CET Time. The test will gauge your level in both maths and computer science and give a chance to win two weeks in a math and computer science summer camp for gifted youth Tech Scouts, taught in English for ages 12-18, held 16-29 of July in Barcelona, Spain.

You can take part in the online test if all the following conditions are met:

  1. Between the ages of 12 to 18,
  2. Have not graduated high school,
  3. Eligible to take part in IOI/IMO 2019.

The top performers of the online contest will be invited for a personal interview to demonstrate understanding of the problems solved during the contest. After the test, the 100 most successful performers will be interviewed, and the top will be awarded a full tuition waiver to attend the advanced level of the Technical Track of Tech Scouts.

Tech Scouts is designed to lay out the foundation of knowledge in mathematics and computer science for the next phase of higher learning. During a two-week intensive training, the students will follow a college level curriculum and discover their passions by getting to know one of Europe’s leading institutions in design, entrepreneurship and technology.

In order to register for the contest, please fill out this type form before 11.59pm May 24. All participants of the contest will get a 25% discount promo code to attend Tech Scouts.


UPD For those of you who cannot meet the required conditions, but would still like to participate, please fill out this form

UPD2 As many of you have informed us of the date coinciding with Google Code Jam round 2, we are moving the date by one week. The new date is May 26. Thank you, everyone!

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By MiptLited, 2 weeks ago, In English,

Hello, Codeforces!

The international competitive programming boot camp Moscow Workshops ICPC is inviting participants! This summer the training program is hosted in different parts of Eurasia on the same dates: July 23-30 2018.


Moscow Workshops ICPC boot-camps are preparing the winners of the ICPC championship: teams who participate in Moscow Workshops events achive the highest results at ICPC World Finals, for instance this year 10 out of 13 teams who won medals at the World Finals were participants of Moscow Workshops ICPC boot-camps.

«Discover Grodno» will be held for the second time on the base of Yanka Kupala State University, the main training platform for competitive programming in Belarus.

«Discover Vladivostok» will be held for the first time. The hosting university will be Far Eastern Federal University. The smart campus of the innovative FEFU is located on the Pacific coast, it’s beautiful environment will inspire students to show impressive results.

During the 8 days of Moscow Workshops ICPC program students’ teams all over the world will prepare intensively for the biggest and the most prestigious competitive championship. Participants will be able to choose between Division B and Division C depending on their skill level.

Division B is for the students who are preparing for the next ICPC season and other international competitions in programming, the training program will be in English.

Division C is for the newcomers to the world of competitive programming and the it’s program will be held in Russian.

The participation cost depends on the date a payment was made and on the region: citizens of the Eurasian Economic Union (EAEU) countries pay in Rubles and others pay in US dollars:

Until June 15 — 23.000 Rubles (for EAEU), $390 USD From June 16 — 27.000 Rubles (for EAEU), $470 USD

The price includes educational program, accommodation on university campuses, meals and sightseeing tour in spare time.

Join Moscow Workshops ICPC! Good luck!

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