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MikeMirzayanov's blog

Codeforces: Results of 2018
By MikeMirzayanov, 6 years ago, translation, In English

Hi Codeforces!

February 2019 is already on the calendar, which means that I was late with the report for 2018. Better late than never! Let's remember last year.

In 2018, cdkrot, 300iq and arsijo joined the team of coordinators. The work of the coordinators is headed (and is the coordinator of the coordinators) KAN. I really hope that a more measured schedule of preparing rounds by a large team of coordinators will give a better insight into the contests. The main innovations in the platform are implemented by me and the developers kuviman, fcspartakm, MaximShipko. Great work on the organization of events and prizes mailing was done by gKseni.

Special thanks to the writers of the problems and testers. It is your content that charges the community with life and unites all of us. Thank you for the problems!

And now let's summarize the 2018th year.

Partner Events

We are pleased to hold programming competitions with companies or for companies. I'm sure this is a great way to support the community of young programmers and hire talented candidates. Here is a list of our main partners this year:

  • Telegram and personally Pavel Durov is supporting Codeforces activities for many years, every regular round is held with their help, thank you!
  • VK, VK Cup — team competition for young Russian-speaking programmers with a series of elimination rounds and finals in St. Petersburg
  • Mail.Ru, Mail.Ru Cup — open individual programming competition, consists of several stages, Technocup — open competition for schoolchildren
  • Harbour.Space University — a series of educational rounds, the selection of summer school Tech Scouts
  • Lyft — a two-level competition with the Final at Lyft headquarters (California) and the mirror contest for worldwide participants
  • Avito, Avito Code Challenge and Avito Cool Challenge — open partnership rounds targeting a wide international audience
  • Microsoft, Microsoft Q # Coding Contest — unusual quantum computing competition
  • AIM Tech — open partnership round targeting a wide international audience
  • Huawei — research competition (marathon) with elements of machine learning
  • IQ Option — private round as a corporate training I hope that in 2019 we will continue to work together with old partners and find new friends. Have you read the post about the XTX Markets initiative?

Major innovations

Work on improvements in Codeforces and Polygon never stops. Much of the work to improve the infrastructure, stability, performance is not evident. The list below lists the main points for noticeable improvements.

Polygon: https://polygon.codeforces.com — platform to prepare programming problems
  1. Improved caching on the test preview page
  2. Assignment a developer to an issue
  3. Add contests to favorites and view only them
  4. Protection against invoker overload by single person/problem
  5. Contest issues tracking
  6. Validation of input/output for custom statement examples using a validator/checker
  7. MathJax support for displaying formulas
  8. Display and edit contests on the problem edit page
  9. Show checker source code in a review mode
  10. Add problems from one contest to other
  11. Support for test groups and tags for solutions
  12. Warning about weak tests in pretests
  13. Improved support of translator role
  14. Support points for tests
  15. API improvements to support test groups
  16. Feature to put binary files (images) as contest resources
  17. Updating dependencies (libraries)
  18. Fixed display of images in the review mode
  19. Unformatted examples in statements via exmpfile
  20. Support of new programming languages
  21. Feature to set a feedback show policies for a test group
  22. Actions block for selected tests on the right-bottom of tests page
Codeforces
  1. Gifts tracking system
  2. Hacks without Flash
  3. Improved support for Russian Olympiads in Informatics stages
  4. Better cheating detection (plagiarism) routine
  5. Read-only mode for spammers/rule breakers
  6. Diagnostics subsystem for C++ undefined behavior solutions
  7. Captcha has been removed
  8. Inputs/outputs/solutions copier by click
  9. Show topic first publish time instead of creation time
  10. Search in Gyms by problem title
  11. MathJax support
  12. Posts reworked (now it is possible to save posts in different languages independently)
  13. User talks improved
  14. Custom problemsets supported, acm.sgu.ru moved on Codeforces
  15. Login by email
  16. Better CSS for complete problemset page (especially print mode)
  17. Add relevant problem tags from Polygon
  18. Better support for unusual "question" problems
  19. HTTPS
  20. Separate untrusted participants for Div 3
  21. Problem ratings
  22. Do not send notifications on your own comments.
  23. Support quantum problems (for MS contest)
  24. Show test results for examples during a round
  25. Better support of printers in groups
  26. Simpler attaching blogs to contests
  27. Support 10 minutes penalty for short ICPC contests
  28. Better support of user forms
  29. Crowdfunding badges in a profile (2015, 2018)
  30. Do not offer coach rights for cheaters
  31. "Less point better" mode for marathon contests
  32. Hide problem tags in virtual contests
  33. New problemset search box
  34. Show live notification (push) on judgment finished
  35. PcmsStandingParser to support NEERC mirror
  36. Introduced m1/m2/m3.codeforces.com minimalistic websites
  37. Format-free examples support
Statistics

Every year I write that I expect stabilization of interest to Codeforces, and every year I am mistaken! So this year we have a significant increase in all key metrics (from 20% to 40%). Probably, the growth of key indicators hints that the end of 2018 could be celebrated bigger. Just look at these numbers!


This year, this image takes into account only completely registered users who have confirmed email.




Only those who participated in rating rounds during July-December are counted. Grew in half.





More than 13 million solutions sent out, + 35% over the last year!




Blog posts with positive score, having at least +5 votes, having at least +20 votes, having at least +100 votes. The total number of posts is not interesting, because a lot of trash/spam, which immediately disappears and the result much depends on how we protect against bots and inadequate. About the same as last year. Write more!




All positive scored comments, having at least +5 votes, having at least +20 votes. A small increase is present.




India increases the lead! Strong growth in Russia, China, Bangladesh, Egypt, USA and Vietnam.




The number of page views, almost + 35% in 2018!




The number of browser sessions did almost + 30% in 2018!




The number of visitors, almost + 25% in 2018, the year!



Not included in the images, but there is a significant increase in the number of hosted rounds (70 → 105) and the number of new problems (516 → 739). Numbers are given in comparison of 2017 and 2018.

I am pleased and proud of the results of Codeforces for the 2018th year. The whole Codeforces team will try to please you in 2019!

— MikeMirzayanov

  • Vote: I like it
  • +871
  • Vote: I do not like it

Comments Comments (37)
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6 years ago, # |
  Vote: I like it +106 Vote: I do not like it

I hope the positive dynamics will not stop and we will enjoy interesting contests and tasks for a long time

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6 years ago, # |
← Rev. 2   Vote: I like it +17 Vote: I do not like it

Hope this year is going to be much better. :)

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6 years ago, # |
← Rev. 2   Vote: I like it +24 Vote: I do not like it

A Good Year has passed! I hope that Codeforces will become better in the new year!

Also, it's the first time that I get to know there is someone else that has BLACK NAME Except from Mike himself :)

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6 years ago, # |
  Vote: I like it +7 Vote: I do not like it

Oh,It's on time.The Chinese New Year beings today.And,always support Codeforces.It's one of the best websits which are for OI.

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6 years ago, # |
  Vote: I like it +86 Vote: I do not like it

Do you consider switching systems to Linux to support 64-bit system?

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    6 years ago, # ^ |
      Vote: I like it +31 Vote: I do not like it

    what will be the pros of using 64-bit system?

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      6 years ago, # ^ |
        Vote: I like it +27 Vote: I do not like it

      int128 :)

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      6 years ago, # ^ |
        Vote: I like it +6 Vote: I do not like it

      I have encountered several TLEs only because I used too much long long. :(

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6 years ago, # |
  Vote: I like it +19 Vote: I do not like it

<3

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6 years ago, # |
← Rev. 2   Vote: I like it +136 Vote: I do not like it

As usual I am asking for it every year :p

We want countrywise standings in each round.

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6 years ago, # |
← Rev. 2   Vote: I like it +50 Vote: I do not like it

No, you are not late, because today is the first day of the lunar calendar 2019. Best wishes for the New Year. QwQ

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6 years ago, # |
  Vote: I like it +1 Vote: I do not like it

Nice! thanks for all the effort,

by the way i think in the "Major innovations" section, "Codeforces" part, item 29, "Crowdfunding budges in a profile (2015, 2018)", the word "badge" should be in place of the word "budge".

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6 years ago, # |
  Vote: I like it 0 Vote: I do not like it

This statistics is just mind blowing!

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6 years ago, # |
  Vote: I like it 0 Vote: I do not like it

What about Romania in countries top?

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6 years ago, # |
  Vote: I like it +94 Vote: I do not like it

Can there be a dark mode for codeforces?

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    6 years ago, # ^ |
      Vote: I like it +32 Vote: I do not like it

    Your profile picture matches the pain of looking to the white screen all day.

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    6 years ago, # ^ |
      Vote: I like it +3 Vote: I do not like it

    well i use "Dark Reader" browser extension for that, it makes every webpage dark (you can set it off for some webpages,...)

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6 years ago, # |
  Vote: I like it +69 Vote: I do not like it

How about the chart with number of "Is it Rated?" comments?

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6 years ago, # |
  Vote: I like it +9 Vote: I do not like it

It is ironic when someone says Thank your for the problems! LOL

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6 years ago, # |
  Vote: I like it -30 Vote: I do not like it

Proud to be an Indian...

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6 years ago, # |
  Vote: I like it +6 Vote: I do not like it

Thank you cf, very cool ! :)

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6 years ago, # |
← Rev. 2   Vote: I like it +6 Vote: I do not like it

I suggest to add more features in standing like AtCoder : see standing of country and search user standing

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6 years ago, # |
  Vote: I like it +10 Vote: I do not like it

In the major innovations section codeforces: 11. MathJax support.

It's working fine on polygon, but I cannot use MathJax in comments, How to enable it?

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6 years ago, # |
  Vote: I like it 0 Vote: I do not like it

This sounds awesome, but IMO Global rounds should be hosted on weekends so more people can join. I ope this gets considered in future rounds.

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6 years ago, # |
  Vote: I like it 0 Vote: I do not like it

A big thank you to codeforces in 2018.

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6 years ago, # |
  Vote: I like it +5 Vote: I do not like it

Hopefully Codeforces will be better in 2019. Looking forwards to more rated rounds.

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6 years ago, # |
  Vote: I like it 0 Vote: I do not like it

In 2018 there were tons of great contests Many thanks for every problem setter :)

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6 years ago, # |
  Vote: I like it +4 Vote: I do not like it

Codeforces will get better and better. Congratulations！

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6 years ago, # |
  Vote: I like it 0 Vote: I do not like it

> India increases the lead

It would be nice to see pie chart by country did different years(so that it's normalized to the size of CF). I'd bet we can see shift to Asia because they have now better timeslot for the rounds, then Europe

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6 years ago, # |
  Vote: I like it -10 Vote: I do not like it

I think the best result of last year is that wery0 began an expert -> wery0!!!!!

And also he has 500+ points on the regional russian olympiad in IT so he will go to IOI this year!!! Let's wish good luck(s*ck) to him

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