Happy New Year!

The New Year is in a two-day distance from us and it's good time to summarize the ending year. In a nutshell, this year's been highly productive for the project. Codeforces has set up large championships, rounds followed one after another, we've launched the Codeforces::Gym project, we've added numerous improvements/fixes/innovations. Here's a short list of our deeds:

• when a user votes for a post/comment, his/her authority is taken into consideration, we've introduced anti-bot and froud-detection heuristics
• the Codeforces::Gym has been opened and has come through many improvements
• the Codeforces Markup, based on Markdown has been introduced, accompanied with special Codeforces tags
• Codeforces helped VK.com to carry out a amplitudinous VK Cup 2012 championship which had around 6000 participants!
• the CROC company has used the Codeforces company to carry out the Open Moscow City and Moscow Region Programming Championship, around 1500 participants!
• the ABBYY company has used the Codeforces platform to carry out the ABBYY Cup 2.0 championship, around 2000 participants!
• we've introduced attaching blog posts to contests as announces, tutorials etc.
• we've semiautomatically attached the tutorials for the past contests
• the Bayan company has used the Codeforces platform to carry out the sorting stage of Bayan Programming Contest 2012/13, more than 3000 participants!
• the CROC company has used the Codeforces platform to carry out the CROC Programming Championship among the Bauman MSTU, around 2000 participants!
• the testlib.h has come through numerous improvements
• we've supported new programming languages
• we've supported the dynamic problem complexity
• we've supported inserting photo albums from Picasa to posts
• we've supported interactive problems — despite the short wording, this point is hugely important
• the Polygon project has come through numerous improvements
• we've supported problems with the score in points and with partial solutions (for the marathon type contests)

And that's not the end! We are glad to demonstrate to you wonderful pictures with pleasing graphs and charts.  

Codeforces registered users growth

The number of contests, yearly statistics (Div. 1 + Div.2 rounds count as two contests)

The number of rounds (competitions), yearly statistics

The number of submissions, yearly statistics

The number of problems, yearly statistics (if a problem occurs in two divisions, it still counts as one)

The number of visits, yearly statistics (according to Google Analytics)

The number of unique visitors, yearly statistics (according to Google Analytics)

The number of page views, yearly statistics (according to Google Analytics)

The graphs of the numbers of visitors in 2011 and 2012 (according Google Analytics, scaled to weekly statistics) — you can easily see the start of VK Cup 2012 there :-)

The distribution of participants by colors (by the end of December, 2012)

And to sum up, let’s compare some points with TopCoder:

A pleasant comparison with TopCoder: the number of participants in the rating (those who have participated over the last 6 months)

The number of contests in 2012 (parallel rounds are taken into consideration for TopCoder)

The number of problems in 2012

As I set my goals in early 2012, I really wanted to make Codeforces the largest site with regular programming contests. The project has achieved this goal. Codeforces is the largest and the most popular regular programming contests in the world!

And at the end of such a pleasant post I sincerely say a huge Thank you! to VK company, which has supported Codeforces for more than two years!

Many thanks to all the team members and writers of the Codeforces problems! We are grateful to the participants and to the authors of posts and comments for your growing interest in the project, and for your loyalty to the interests of programming contests!

Mike Mirzayanov, Codeforces CEO and Founder