MikeMirzayanov's blog

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

April 19, 15:35 (UTC) the VK Cup 2018 - Wild-card Round 2 will start.

Participants are invited to achieve progress in solving an unusual problem. VK Cup teams which were advanced to the Round 2 (and didn't advance to the Round 3) will take part in VK Cup 2018 - Wild-card Round 2 officially. In addition, this round will be open to the public for unofficial participation for everybody. Registration will be open for the whole round duration.

The round will be one week long. After the end latest submission (with positive score) of each participant will be judged on system tests.

Good luck!

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

Hello Codeforces!

On April 10, 14:35 UTC Educational Codeforces Round 42 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 Div. 2. 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 me and Alex fcspartakm Frolov.

We'd like to thank Nikolay KAN Kalinin, Grigory gritukan Reznikov, Vladimir Vovuh Petrov for the testing and help in preparing the round.

Good luck to all participants!

UPD: Some information from Harbour.Space U

The third Hello Programming Bootcamp finished as teams from around the world learned, competed, and got to know each other in the cities of Kollam and Moscow.

“I'm positively surprised with the level and number of Indian teams. I believe when following a systematic and regular training schedule — they will certainly attend top world records in programming” says Mike MikeMirzayanov Mirzayanov.

The results of the India boot camp are as follows:

We would like to congratulate the top teams from the India side in both divisions A and B — and especially recognise division A’s winner: Team SDV — Vasily platypus179 Alferov, Vaibhav gvaibhav21 Gosain, Motasem Motarack AL-Kayed sponsored by Social Discovery Ventures, and winners of the Educational Codeforces Round 39.

The division A winners are: Team SDV (platypus179, gvaibhav21, Motarack), TheVindicators (IIIT Kharagpur) (evil666man, Chenghiz), DomiNUS (NU of Singapore) (vodanhna, darknsux, minh141198).

The division B winners are: BEU Programmers (Baku Engineering University) (mahmud2690, Mamedov, fuck_coderinuse), Penza State University (Fortin, WooDeND, Key_J) and Sab_lite_hai (IIT(BHU),Varanasi) (Enigma27, Dsingh_24, nitishk24).

All results from India side
All results from Russia side

From the ever present in ACM World Finals city of Moscow, to the new-comer on the world stage city of Kollam — Hello India x Russia Programming Bootcamp showcased heart, passion, and a universal drive towards a better competition.

“It's the first time I participate at Hello ACM-ICPC Bootcamp in Asia and I admire local hospitality and students motivation. Everyone seems to be eager to learn, participants stay very late upsolving the contest problems and revising the topics they were thought during the day” states Gleb GlebsHP Evstropov, The Coordinator of the Programming Committee.

The latest in world finals simulation training would not be possible without the bronze sponsorship of VTB, the institute with the most extensive international network of any Russian bank, boasting more than 30 banks and financial companies in more than 20 countries.

Fill out this form and we will keep you up to date on our next boot camp!

UPD: Tutorial

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By MikeMirzayanov, 2 months ago, In Russian,

2 марта в 18:35 начнётся второй квалификационный раунд чемпионата VK Cup 2018!

Правила этого раунда будут совпадать с правилами Квалификации 1. К участию приглашаются команды, не участвовавшие в первой квалификации или набравшие в ней менее 2600 баллов. Те, кто успешно справился с первой квалификацией, могут принять участие вне конкурса, при этом их результаты никак не будут влиять на проход остальных команд. Разумеется, от команд, участвующих вне конкурса, также требуется соблюдение всех правил Чемпионата.

Для участия в раунде сначала необходимо зарегистрировать команду в чемпионате по ссылке:

Зарегистрировать команду на Чемпионат →

Затем следует зарегистрироваться на Раунд:

Зарегистрироваться на Раунд →

Раунд продлится 24 часа, такая продолжительность выбрана для того, чтобы все нашли себе удобное время для участия. Квалификационный раунд, как и все предстоящие раунды, требует отдельной регистрации, она будет открыта на протяжении всего раунда.

При регистрации на раунд состав вашей команды фиксируется и не подлежит дальнейшей модификации. Вы не сможете в будущем добавить или удалить члена команды. Пожалуйста, перед регистрацией убедитесь, что у вас нет желания изменить состав. Состав команды не сможет быть изменен, даже если вы отмените регистрацию на квалификационный раунд.

В Раунд 1 пройдут все команды, которые наберут положительное количество баллов, не меньше количества баллов у команды на 500-м месте.

Во время квалификации задачи тестируются системой только на претестах, а системное тестирование состоится после окончания раунда. Обратите внимание, что претесты не покрывают все возможные случаи входных данных, поэтому тщательно тестируйте свои программы! Взломов, падения стоимости задач во время квалификации не будет. Время сдачи задач не будет учитываться, однако будут учитываться штрафные попытки.

Категорически запрещается публиковать где-либо условия задач/решения/какие-либо мысли и соображения о них до окончания раунда. Запрещено обсуждать задачи с кем-либо, кроме вашего сокомандника. Будьте честны, пусть в Раунд 1 пройдут сильнейшие!

После окончания раунд станет доступен всем для дорешивания, а его задачи попадут в архив, в том числе и на английском языке.

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By MikeMirzayanov, 2 months ago, In Russian,

Всем привет!

24 февраля в 18:35 начнется первый квалификационный раунд чемпионата VK Cup 2018!

Раунд продлится 24 часа, такая продолжительность выбрана для того, чтобы все нашли себе удобное время для участия. Квалификационный раунд, как и все предстоящие раунды, требует отдельной регистрации. Регистрация уже открыта и будет открыта на протяжении всего раунда. Результаты раунда не влияют на рейтинг Codeforces.

При регистрации на любой из квалификационных раундов состав вашей команды фиксируется и не подлежит дальнейшей модификации. Вы не сможете в будущем добавить или удалить члена команды. Пожалуйста, перед регистрацией убедитесь, что у вас нет желания изменить состав. Состав команды не сможет быть изменен, даже если вы отмените регистрацию на квалификационный раунд.

Если вы пока не уверены в текущем составе команды, то не регистрируйтесь на предстоящий раунд. Если вы не будете участвовать в первой квалификации или не пройдете по ее результатам в Раунд 1, то вы сможете попробовать свои силы во второй квалификации.

Чтобы пройти в Раунд 1, вам надо принять участие хотя бы в одной из квалификаций. Из каждой квалификации в Раунд 1 проходят все команды с положительным числом баллов, которые набрали не меньше баллов, чем команда на 500-м месте.

Во время квалификации задачи тестируются системой только на претестах, а системное тестирование состоится после окончания раунда. Обратите внимание, что претесты не покрывают все возможные случаи входных данных, поэтому тщательно тестируйте свои программы! Взломов, падения стоимости задач во время квалификации не будет. Время сдачи задач не будет учитываться, однако будут учитываться штрафные попытки.

Категорически запрещается публиковать где-либо условия задач/решения/какие-либо мысли и соображения о них до окончания раунда. Запрещено обсуждать задачи с кем-либо кроме вашего сокомандника. Будьте честны, пусть в Раунд 1 пройдут сильнейшие!

Результаты раунда не будут влиять на рейтинг, внеконкурсное участие в раунде не разрешается. Однако, после окончания раунд станет доступен всем для дорешивания, а его задачи попадут в архив в том числе и на английском языке.

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

Hello!

As an allowed language on Codeforces and Polygon C++17 has been added. The compiler we use is 32-bit mingw64 version 7.2.0 (later will be updated when new versions are released). We are using a patch from halyavin to speed up I/O when using scanf/printf (for more details, read here). The exact used distribution can be installed on Windows from our package manager called PBOX using the link http://pbox.me/packages/mingw-w64-7

The exact compilation command line is:

g++.exe -static -DONLINE_JUDGE -Wl,--stack=268435456 -O2 -std=c++17 -o %name%.exe %1 2>compilation.log

Wish you successful solutions in C++17,
MikeMirzayanov

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

Добрый день!

Прямо сейчас идет первый тур олимпиады. Посылаю участникам лучи интеллекта и внимательности! Надеюсь, и задачи и результаты вас порадуют.

Предлагаю в комментариях обсудить задачи (когда тур завершится во всех регионах) и результаты.

Наверное, в этом году большинство регионов проводит на Яндекс.Контесте. Интересно, многие ли регионы проводят самостоятельно?

Желаю всё решить, успеть оттестировать и получить максимальные баллы!

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By MikeMirzayanov, history, 4 months ago, In English,

Hi!

After the Educational Codeforces Round 35 (рейтинговый для Див. 2) the system marked some solutions as plagiarism by mistake. It counts submitted twice solutions of the same participant as a plagiarism. Sorry about it. Day ago I rolled back punishment and judged such submissions as normal. Now I'm fixing the ratings. In 2-3 hours some rating changes will be reverted and applied back. The same with NY magic. Temporarily magic is unavailable now. It will be back soon!

The changes will affect ~10 people.

MikeMirzayanov

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By MikeMirzayanov, 4 months ago, translation, In English,

Happy New Year, Codeforces!

I hasten to wish the whole community (and including me) correct programs, sudden insights, beautiful ideas and interesting problems!

I hope that you have met the new year at least as fun as I am. Have you had enough sleep after New Year's Eve? This year, the traditional post summarizing the past year, I sat down to write only on January 1, 2018. I hope that I will not have to sum up the whole year.

This post is important to me, since it draws a line to all the work done by the Codeforces team and the entire community in 2017. Many thanks to the team: all of the achievements listed below are the result of joint efforts. We did an excellent job! The community must know its heroes. In 2017, MikeMirzayanov, KAN (problem coordinator), gritukan (second problem coordinator), netman (ex-second problem coordinator), kuviman (developer), fcspartakm (developer), SladeThe (developer) and gKseni (manager). Great contributions were provided by the students of the Saratov University: BledDest, PikMike, Vovuh, and Perforator — educational rounds, trainings in Codeforces::Gym and help in the development. I radiate the rays of gratitude to problem writers and testers: you create interesting content for many thousands of programmers from all over the world. Many thanks to all those who helped with the special projects, wrote interesting posts and good comments. All together, we were able to make Codeforces better!

So, let's move on to the results. It seems to me, this year again has something to brag about.

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By MikeMirzayanov, 4 months ago, translation, In English,

Do you already have a New Year's mood?

And we have traditional gifts!

Change handle feature

Hurry! Only until the 10th of January, you can change your handle (but only once)! Note that it will be possible to roll back the changes or change the handle again only after a year. Be careful what you wish for.

You can change your handle to the new one which wasn't used before by anybody or which was used by you before. The links to a profile page with old handle would automatically redirect to the actual profile.

This year we have an improvement. If you took part in at least 10 rounds you can request handle of an inactive participant. It means that the participant should have a period of activity on Codeforces of at most 30 days, this period should be in 2012 or earlier. The inactive participant can’t have posted comments, messages and so on. It can’t take part in more than 2 contests. It will be automatically renamed and informed by email. If you can’t change handle to others, it means that some requirement doesn’t meet. Please do not ask me to do something with it. I’m not Santa Claus.

Talking about handles I always reminisce the following story. Once a user wrote me the message: "Please change my handle from I_love_Valya to I_love_Sveta, as I no longer love Valya ..."

New Year's masquerade of colors and ranks

Traditional magical tab has appeared in the profile setting. Happy New Year!

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By MikeMirzayanov, 4 months ago, In Russian,

Привет, Codeforces!

Перед полуфиналом ACM-ICPC у меня возникла неожиданная мысль воспользоваться моментом и взять интервью у самого успешного тренера в истории чемпионатов по программированию (ACM-ICPC) Андрея andrewzta Станкевича. Было интересно попробовать и себя в новом качестве. Мне кажется, Андрей рассказал много интересного. Спасибо!

Если вам было интересно, то оставляйте в комментариях ваши предложения с кем было бы интересно побеседовать в следующие выпуски. Приятного просмотра.

Спасибо Андрею за интересный рассказ и ИТМО за предоставленную возможность и помощь.

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By MikeMirzayanov, history, 4 months ago, translation, In English,

Hello, Codeforces!

I want to test the system before the rated rounds based on Technocup stage, to be sure that everything works as expected.

I invite you to take part in Testing Round #14 (Unrated). It will start soon, on December, 22, 11:05:00 (UTC). It will be unofficial unrated round. The duration is 90 minutes.

Pretests are unusually weak to trigger more hack.

Thank you,
MikeMirzayanov

UPD: Thank you for participation. I didn't notice any bugs. It seems we are ready for new rounds!

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By MikeMirzayanov, history, 5 months ago, translation, In English,

Hi, Codeforces!

This is not an ordinary post from me. This is not an announcement of new features or a championship, but I'm no less enthusiastic.

I am glad to inform you that from January 29 to February 16, 2018 I will be giving the course "Advanced Algorithms and Data Structures" in Harbour.Space University (Barcelona, Spain). The course will be in English. The students of this course will not only be students of Harbour.Space, but is open to all! Who wants to join?

This course isn't just for Harbour.Space students, it is also open to Codeforces participants, who will be offered a special price, 1000 EUR. The cost does not include travel or accommodation.

Register for the Course →

In my plans there is a detailed story about some algorithms and data structures, a lot of practical exercises and emphasis not only on the correctness, but also the beauty and structure of the code. My goal is to make useful and interesting classes for both those who want to understand the fundamental CS, and for those interested in programming competitions. And of course, we will have the opportunity to meet and talk. I'm happy to share stories about the history of Codeforces and development plans.

The course will consist of three weeks of training, 5 training days in each week. The program includes daily lectures and practical exercises. It will not be boring for sure!

Here is the expected course outline:

Week Day Topics
1 1 Heap data structure, heap properties and operations. HeapSort. Priority queue. Other heap applications. Mergeable heaps: binomial heap, pairing heap, randomised meldable heap.
1 2 Fenwick tree. Description and motivation. Implementation of Fenwick tree. Generalisation for higher dimensions. Skip list data structure. Implementation details. Indexable skiplist.
1 3 Segment trees. Top-down implementation. Bottom-up implementation. Segment trees applications. Persistent data structures. Persistent stack, persistent array. Persistent Fenwick and segment trees.
1 4 Cartesian trees, treap data structure. Merge and split operations. Treap implementation in detail. Treap applications.
1 5 Treaps with implicit keys. Ropes. Segment reverse operation. Examples of problems.
2 6 Introduction to strings. String searching (matching) problem. Pattern pre processings. Z-function, prefix-function. Their applications. Knuth–Morris–Pratt algorithm. Matching finite state machine.
2 7 Multiple pattern matching. Trie data structure. Aho-Corasick algorithm. Implementation details. Dynamic programming on a trie.
2 8 String hashing. Rabin-Karp algorithm. Fast substrings comparison with hashes. Suffix array. LCP array. Efficient construction algorithm. Applications.
2 9 Suffix tree. Ukkonen's algorithm. Suffix tree construction from LCP array. Suffix tree applications.
2 10 Suffix automaton. Size bounds. Linear Algorithm. Using suffix automata as an index for approximate string searches.
3 11 Introduction to automata theory. Formal languages. Context-free languages. Formal grammars. Context-free grammars. NFA, DFA, convert NFA to DFA. Build automaton by regular expression.
3 12 LL(1) parser. Arithmetic expressions parsing. Shunting-yard algorithm. Simplified Pascal language parsing and interpretation.
3 13 Algorithms for traversing a graph. DFS. Properties. DFS search tree. Edges classification. Linear bridge-finding algorithm. Linear articulation points finding algorithm. Strongly connected components. Tarjan's strongly connected components algorithm.
3 14 Tree problems. Bottom-up approach. LCA problem. LCA algorithms.
3 15 Bipartite graphs. König’s criterion. Problems: maximum matching, minimum edge cover, maximum independent vertex set, minimum vertex cover. Connection of the problems. Berge's lemma. Kuhn algorithm. Kuhn algorithm properties. Minimal vertex cover by maximum matching. Cover DAG by minimal number of paths.

Harbor.Space University is located in Barcelona (Spain). For users of Codeforces, Harbour.Space is known for active participation in the life of the community of sports programming (partnership with Codeforces in the framework of Educational Rounds). The main activity of the university is teaching (there are bachelor's and master's programs) in the following areas:

  • Maths as a Second Language
  • Computer Science
  • Data Science
  • Cyber Security
  • Interaction Design
  • Digital Marketing
  • High Tech Entrepreneurship
  • FinTech
  • BioTech
  • Aerospace Engineering
  • SuperCities UrbanTech

Register for my upcoming course here.

Mike Mirzayanov

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By MikeMirzayanov, 5 months ago, translation, In English,

Hello!

I am pleased to report that two rounds of Codeforces have gone quite well in terms of the work of Codeforces, I am very glad about it. These days nights I spent in a profiler, fixing the code, researching the settings of MariaDB.

In addition, I managed to allocate several hours on Sunday (to be honest, until Monday morning) to finish the long-planned innovation.

Meet, diagnostics of solutions in C++!

Many Codeforces visitors are already tired of the questions of less experienced participants: "Why does my solution not work on some test on the Codeforces servers, if I locally launch it and it works correctly? You have the wrong compiler/servers!" In 99% of cases this is an example of undefined behavior in a program. In other words, the program contains mistakes that, due to a number of circumstances, are not reproduced at local launch, but are reproduced at launch on the Codeforces servers.

Sometimes, it's not easy to notice such a mistake. A small overflow of the array can lead to an incorrect answer on the test and to an runtime error of the program.

In g++/clang++ there is a remarkable tools called sanitizers. It's such a way to compile a program in a special mode so that when it's working, it will check it for undefined behavior (and some other errors) and, if any, print them to stderr. The drmemory (it is similar to valgrind, but for Windows) has similar functionality, which starts the program in a special mode to detect errors. With such two diagnostic launches, the performance of the program suffers tremendously (the program is executed 5-100 times slower and requires more memory), but often it's worth it.

Now automatic diagnostics in some cases will prevent a question like "Why does not work ???", indicating the error or its appearance!

If your solution:

  • written in C++,
  • finishes with a verdict "wrong answer" or "runtime error"
  • on this test worked extremely quickly and consumed a little memory,

then it will be restarted using special diagnostic compilers (clang ++ with sanitizers and g++ with drmemory). If an execution error occurs during this launch, the diagnostics log will be displayed in the test details in the "diagnostics" section. Of course, this entry will contain a technical report in English, but often it will indicate to you the error of the program. Often it contains the cause of the mistake and even the source code line. If the diagnostics are not displayed, then at least one condition above is not fulfilled or the diagnostics has not detected any errors.


Example of the diagnostics:  here it is written that there was an array out of range error in the line 78.

Thus, the diagnostics will sometimes help you to find a mistake like "out of bounds error", "signed numbers overflow", "uninitialized variable", etc. Carefully read the diagnosis and do not make such mistakes in the future!

I wish your programs did not fail. I hope the innovation will be useful!

There are big plans as it is useful to apply such diagnostics. Do not go far, wait for news, soon there will be more innovations!

P.S. Also, diagnostic compilers are simply available for use. For example, you can use them on the "Custom invocation" tab. I recall that the program runs many times slower and consumes more memory in diagnostic mode.

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By MikeMirzayanov, 5 months ago, In English,

The contest is declared unrated. For Technocup, results of this round will be counted for elimination. Also, we plan to hold one more (the fourth) elimination round to compensate this failure. Stay tuned for updates. We apologize for the situation, hope you enjoyed the problems.

Hello.

If you are upset about today round, I understand you. Please, downvote this blog instead of the official announcement. The coordinator, writers and tester did a great job making the round. But technical issues erased their effort.

The chain of technical issues leaded to so bad work of the website. This week our server with Polygon system had broken and Mail.Ru quckly replaced it with another one. I forgot to reconfigure Polygon on the new server and it leaded to 502 during the contest. Also today one Codeforces server stopped to respond and I do not know the reason yet (it is first time issue with this server).

Right now I feel myself very upset and thinking about the way to change an approach to have enough time to setup, monitor and develop the system.

Sorry again about it.

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

Hello!

ACM-ICPC Southern Subregional Contest (NEERC/Northern Eurasia) 2017 has ended on October 18. There were 73 teams onsite in Saratov, most of them were invited because of their result on the qualification stage.

On Saturday, October 21, 08:05 (UTC) will start online-mirror 2017-2018 ACM-ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred).

I invite ACM-ICPC teams and individual participants of Codeforces competitions to take part! Sure, the contest will be unrated.

MikeMirzayanov

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By MikeMirzayanov, 6 months ago, In English,

Codeforces Round 440 will start on October 15 (Sunday), 08:05 (UTC). It will be based on Technocup 2018 Elimination Round 2. So, if you are a Russian-speaking high-school student, please take part in the Technocup 2018.

Codeforces Round 440 is open and rated for everyone.

Wish you good luck and bugless code.

Editorial is posted.

Congratulations to winners!

Technocup official round:

  1. Horoshi_chelovek
  2. scanhex
  3. Krisha
  4. ZinchenkoDanil
  5. neckbosov

Div. 1:

  1. khadaev
  2. Errichto
  3. eddy1021
  4. FizzyDavid
  5. fateice

Div. 2:

  1. wdmmsyf
  2. oscillation
  3. pulkit.kapoor
  4. oscar172772
  5. OMS

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

Hello, Codeforces!

I'd like to invite you to Codeforces Round #436 (Div. 2). It'll be held on Monday, September 25 on 10:35 UTC and as usual Div. 1 participants can join out of competition. Note that round starts in the unusual time!

This round is held on the tasks of the school stage All-Russian Olympiad of Informatics 2017/2018 year in city Saratov. They were prepared by Perforator, MikeMirzayanov and fcspartakm. Many thanks to the testers: sdya и BledDest, and coordinators KAN and gritukan.

It will be a little unusual round — you will be given six problems and two hours to solve them.

Good luck and have fun!

Congratulations to winners!

Div. 2:

  1. ZJT_NOI2017_AK
  2. AngusRitossa
  3. Jha_The_ME_Coder
  4. cxh007
  5. Alexvsalex

Div. 1:

  1. Shik
  2. dreamoon
  3. black_horse2014
  4. orbitingflea
  5. NiroBC

Analysis is here.

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By MikeMirzayanov, history, 7 months ago, In English,

Welcome to 2017-2018 ACM-ICPC, NEERC, Southern Subregional Contest, qualification stage (Online Mirror, ACM-ICPC Rules, Teams Preferred).

The contest was held yesterday on September 17. Mostly it is focused on the participants of the Div 2.

Note that you can print PDF (English or Russian) with the statements. It will be available on the contest dashboard page on the right.

Good luck!

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

I apologize to the participants of the round. It happened that I accidentally had run improper script and it rebooted the judging machines. It is very insulting, because most problems were proposed by me and I hoped to host an interesting competition for you. A lot of effort was spent on preparation. Apparently, the mistake of just such a human character happened for the first time. I really hope not to repeat it in the future.

MikeMirzayanov


Want problems? We have some!

Codeforces Round 434 will start on September 17 (Sunday), 13:05 (UTC). It will be based on Technocup 2018 Elimination Round 1. So, if you are a Russian-speaking high-school student, please take part in the Technocup 2018.

Many thanks to KAN, 0n25, Ne0n25, ifsmirnov, irkstepanov and white2302 for their help in round preparation. Some problem ideas are mine.

I hope you will like problems. There will be 6 problems in div. 2 and 5 problems in div. 1.

Wish you good luck and bugless code.

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By MikeMirzayanov, history, 7 months ago, In Russian,

Mail.Ru Group совместно с МФТИ, МГТУ им. Н. Э. Баумана и Codeforces в третий раз запускает Технокубок — совместную олимпиаду по программированию для школьников. В этом учебном году олимпиада вошла в перечень олимпиад школьников, повысив свой уровень до второго — круг учебных заведений, дающих льготы победителям и призерам, значительно расширился. Лучшие участники получат ценные призы от компании Apple.

Сразиться за звание самого талантливого молодого программиста приглашаются учащиеся средних образовательных учреждений 8 — 11 классов.

Победители и призеры олимпиады будут определены по результатам очного этапа, который будет проведен в Москве весной 2018 года на базе площадок МГТУ им. Н.Э.Баумана и МФТИ.

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By MikeMirzayanov, 8 months ago, In Russian,

Больше контестов хороших и разных! Вдохновившись рассказами MikhailRubinchik об успехах проведения квалификационных этапов в Восточном четвертьфинале NEERC, в этом году и Южный (саратовский) четвертьфинал объявляет о проведении квалификационного этапа. В октябре состоится 20-й юбилейный четвертьфинал в Саратове. Надеемся, что проводя квалификацию, мы сумеем дать возможность большему количеству команд попробовать себя в соревнованиях по программированию.

Для широкой аудитории 17-го сентября будет проведено онлайн-зеркало на Codeforces. Приглашаются все!

В этом году (сезон 2017-2018) Четвертьфинал ICPC Южного подрегиона NEERC будет содержать дополнительный квалификационный этап. Дата проведения — 17 сентября 2017 г. До 11 сентября необходимо зарегистрировать команду на сайте https://icpc.sgu.ru.


Зарегистрироваться →
Для команд Южного подрегиона NEERC

Приглашаются команды студентов/магистрантов/аспирантов из Астраханской, Белгородской, Волгоградской, Воронежской, Курской, Липецкой, Нижегородской, Пензенской, Ростовской, Самарской, Саратовской, Тамбовской, Ульяновской областей, Краснодарского, Ставропольского краёв, республик Адыгея, Дагестан, Кабардино-Балкария, Калмыкия, Карачаево-Черкесия, Чечня, Марий Эл, Мордовия, Северная Осетия, Татарстан, Чувашия. Команды должны состоять из трёх студентов/магистрантов/аспирантов (ниже смотрите формальные требования), представляющих один вуз. Участие в квалификационном этапе бесплатное. Оргвзнос не предусмотрен.

Этап будет одновременно проведен на нескольких площадках в ряде городов Южного подрегиона NEERC. Продолжительность квалификационного этапа 4 часа, язык условий — русский. Будет доступен перевод условий на английский язык.

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By MikeMirzayanov, 11 months ago, In English,

Hello, Codeforces!

I am pleased to announce the 2nd Hello Barcelona Programming Bootcamp in collaboration with Moscow Workshops ACM ICPC, which will be hosted by our partner Harbour.Space University together with Moscow Workshops ACM ICPC, ITMO University, Moscow Physics and Technology University, Saint Petersburg State University and Codeforces!



The boot camp will be held from September 27th to October 5th in Barcelona. This time it will be at the beautiful and technologically mind-bending Media-TIC building — the Smart Building of Tomorrow.



Media-TIC building — the Smart Building of Tomorrow

The world's greatest coaches will be attending: Andrew andrewzta Stankevich, Michael Endagorion Tikhomirov, Gleb GlebsHP Evstropov, Artem VArtem Vasilyev and other world renowned Russian coaches. As a coach, I will come too. The Chief Judge of the camp is Oleg snarknews Khristenko. Seriously, it will be a unique opportunity for teams around the world to learn from such well-known and successful coaches in the ACM-ICPC world.

Having visited the first Hello Barcelona programming Bootcamp in February, I left the event feeling inspired from the overall atmosphere. I am sure that all teams received an immense amount of knowledge and skills. As one of the coaches, all of the flattering reviews about the camp from the participants were pleasant for me to hear. I am very glad that these camps are becoming regular. Harbour.Space University and Moscow Workshops ACM ICPC have done a job worthy of admiration!

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. 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.

The participation fee is unchanged: €1270 per person (cultural program, accommodation and half-board meals included).

Single participants and teams must register by July 1st, 2017 to receive the 15% off-Early Bird Discount, or the 20% off-Loyalty Discount, which is awarded to teams that participated in previous Moscow Workshops ACM ICPC boot camps.


Learn more about Barcelona ACM-ICPC Bootcamp

You can ask any questions by email: hello@harbour.space

Hope to meet you on the Bootcamp, Mike Mirzayanov

In order to experience the atmosphere of the event, I suggest you familiarize yourself with the photos and videos from the 1st Hello Barcelona programming Bootcamp in collaboration with Moscow Workshops ACM ICPC.

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By MikeMirzayanov, 11 months ago, In Russian,

Общая информация

Саратовский государственный университет в первой половине августа проводит международную летнюю студенческую школу по программированию. Продолжительность школы — десять дней, школа пройдет с 31-го июля по 10-е августа 2017 года.

К участию приглашаются как команды из двух-трех человек, так и индивидуальные участники.

Школа пройдет в живописном месте, на одной из саратовских баз отдыха на берегу Волги. Участники будут расселены в уютных номерах по 2-4 человека и обеспечены трехразовым питанием. На территории базы имеется собственный пляж и спортивные площадки.

В программе школы запланировано 10 рабочих дней, включающих ежедневные пятичасовые тренировки, разборы задач, дорешивания. Будет прочитана серия лекций. Учебная программа рассчитана на студентов, которые хотят достичь значительных успехов на соревнованиях по программированию.

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

ACM-ICPC World Finals 2017 will begin on May 24, 2017 at 15:00 (UTC). This event is the main event of the year in the world of sports programming!

This year ICPC Regional participation included 46,381 of the finest students and faculty in computing disciplines from 2,948 universities in 103 countries on six continents. A record 50,145 students and 5,073 coaches competed in ICPC and ICPC-assisted competitions this year, setting new records in participation.

Codeforces wishes the teams to show a vivid and interesting contest contest. We wish to find beautiful solutions, write without bugs and enjoy many accepted problems!

Links:

ACM ICPC World Finals 2017 English Broadcast:
ACM ICPC World Finals 2017 Indian Broadcast:
ACM ICPC World Finals 2017 Chinese Broadcast:
ACM ICPC World Finals 2017 Arabic Broadcast:
Broadcast from legends: Petr, tourist, Endagorion:

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

Hello, Codeforces!

The ACM-ICPC World Finals 2017 event is running now. Tomorrow will be the main contest. During these days the directorate of ACM-ICPC shared some news.

  • Let me remind you that this season (2016-2017) is last, when the general sponsor of the championship is IBM. For 20 years, IBM has supported ACM-ICPC, investing millions of dollars annually. Thank you, IBM! At the moment, the model is actively being worked out, when there will be not one general sponsor, but there will be a fund in which several companies will participate. At the opening ceremony the Sport Programming Foundation was mentioned. I believe this Foundation will be the main one for the future seasons of the championship. However, these are not yet close plans.

    It was announced that the next three years the general sponsor of ACM-ICPC will be JetBrains! This is amazing news. Particularly pleased that this is actually a Russian company, and its executive director Maxim Shafirov coached the team of St. Petersburg State University, which became the world champion in 2000! I'm sure that the wonderful development environment from JetBrains in the future finals of the championship will await us as a pleasant bonus.

  • There is a reform of the qualifying stages of the championship. For example, now Rissian+ regional contest (NEERC) is not part of the European Regionals, but is a separate league of the Northern Eurasia. In general, eight leagues (read, super-regions) were singled out: Europe, Northern Eurasia, North America, Latin and South America, two leagues in Asia, Africa and probably Australia and Oceania. It is planned that each league will have its own separate finals with medals and the top 12 teams from each league will receive a ticket to the World Finals. While these are still distant plans, but the first steps have already been taken. Discusses its quota on the number of participations in the league finals (3 times).

  • Unfortunately, this year a significant part of the teams did not receive a visa at all (5 teams) and a dozen more could not arrive completely because of the visa problems of one of the participants. Saratov State University, apparently, is among them. It was announced the decision to invite to the next Wold Finals without any selections and quota accounting for 5 teams that could not come this year. In addition, it is proposed to give a +1 year to participate (without taking into account any other requirements) to all teams that could not arrive completely.

  • The next Finals will be held in Beijing, and a year later — in Kochi (India).

Such news.

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