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