Hi.

Codeforces round #299 is gonna take place soon(exact time) and I'm the writer. I'm lucky to be the first Iranian author in Codeforces, in your and our new year (2015 and 1394).

Now, I wanna thank: myself(PrinceOfPersia) for writing the problems(:P), MikeMirzayanov for great Codeforces and Polygon platform, Zlobober and Damon and sobhan.miryoosefi for helping me prepare this round, Haghani and SoroushE for testing this round, Delinur for translating problem statements into Russian and big thanks to my great buddy, HosseinYousefi for problem legends and the pictures.

Also, I wanna thank MinakoKojima for teaching me how to use polygon and testlib and so much other things about it (about a year ago).

This is my first official contest(after all those contests in Gym :D). I hope you enjoy it.

The main character of all problems is Tavas, well-known by eating CoffeeMix without water! Trust me, when he does that it smells awful.

Also, you'll meet his friends.

I hope you enjoy the problems. I wish you all high ratings, many Accepted solutions and Successful hacking attempts. And Hacked instead of Failed System Test.

Scoring will be posted later.

GL & HF ;)

UPD: Scoring will be standard for both divisions (500-1000-1500-2000-2500).

UPD2: Contest is over. We're waiting for system testing. Editorial is published.

UPD3: System test is done. Congratulations to all winners.

Div.1 winners:

1. jcvb
2. rng_58
3. vepifanov
4. mmaxio
5. flydutchman

And Div.2 winners are:

1. l1n4r
2. 0e352a
3. vintage_Vlad_Makeev
4. wilcot
5. boray

Good job everyone, see you ;)

Hello, Codeforces!

I'd like to invite you to Codeforces Round #298 (Div. 2). It will be held on Sunday, April 12 at 19:00 MSK and Div. 1 participants are invited to join out of competition.

Problems have been prepared by Maxim Mescheryakov (Neon) and Danil Sagunov (danilka.pro). We hope you'll find them interesting.

Great thanks to Maxim Akhmedov (Zlobober) for helping us preparing the contest, to Maria Belova (Delinur) for translating the statements into English, to Mike Mirzayanov (MikeMirzayanov) for the great Codeforces and Polygon systems and ideas of some problems. Also thanks Vitaliy Aksenov (Aksenov239) for writing solutions.

You will be given six problems and two and the half hours to solve them.

UPD: Scoring system 500-1000-1500-2000-2500-3000

UPD2: Competition completed! Thank you all!

UPD3: Congratulations to the winners!

1. xuanhien070594

2. misis

3. Mikagura_Seisa

4. plem

5. 11111111

UPD4: Editorial here

Hello Codeforces.

This is a really good and pleasant day for us. We are happy to announce that the fundraising campaign on Codeforces is successfully completed and its results are even beyond our expectations. Thank you for your support, your trust and your kind words.

By the way, we have some more unprocessed PayPal transfers: for unknown reasons the notifications in some cases didn't contain some data needed to process them automatically. We will process them manually and update the data as soon as possible.

To all of you waiting for our present in the mailbox, please update your Codeforces profile information or make sure that it already is complete and up-to-date.

Thanks!
Mike Mirzayanov

Hi!

It is only a day before the end of the fundraising campaign dedicated to the 5th anniversary of Codeforces. We are glad and grateful for your help and support. We are working hard to justify your and our own expectations.

For those who are not accustomed to rush, remember that you still have a little time to join the remarkable list of our friends — help us and get a gift from the Codeforces team!

When summing up, of course, we mostly want not to count money, but to assess progress and the work done. I looked at all of our commits to Codeforces and Polygon, and made a digest of changes.

I did not include to the digest improvements in the depths of system's backend (although stability progress should be visible), infrastructure jobs, org. work around the championships — but, believe me, there were many items too.

And here is the list of our achievements for about two months after anniversary.

Hello everybody!

Our company wants to say thanks to Codeforces and congratulate it with the 5 years birthday:)

A year and a half ago I and the team (Sfairat, olpetOdessaONU, Sklyack) met Victor Shaburov and became co-founders of Looksery. We work in Computer Vision and Augmented Reality areas.
On behalf of all our collective I want to say thanks to MikeMirzayanov and Codeforces team, you do a great matter, and I'm sure it will have a huge impact on the IT segment of the nearest future. To tell the truth, I don't know how we would be able to solve the problems that we had at the beginning of Looksery path if there were no Codeforces or ACM ICPC in our lives.
I would like to tell a few words about our organization, clarifying my opinion about popular topic of the last few days about competitive programming and "real" job.
In Looksery, most of the competitive programmers work on the "core" functionality, but you can also find them in each of the Android, iOS and Backend departments.
During the work on the project we've found out that Computer Vision is a field where ability to write optimized code and skills of solving the problems, which haven't ever been solved before, are extremely required.
Those, who have iPhone4S (or higher) or device with Android 4.3+ may take a look at our application by this link
At the end of this fall we've successfully launched iOS app, got 2 000 000 users, become top 1 overall in Mexica and Best App of Year by Vogue :) Recently we have launched Android app.
You could see a short demonstration of our product below. The video was created in our app on iPhone 6+:
We are happy that now in our team are Sfairat, olpetOdessaONU, Sklyack, tiirz, LesyaPhoenix, MrDindows, Rubanenko, Krasnokutskiy, 2222, Maxim, Avalanche, Igor_Kudryashov, Kepnu4, and many others.

We will prepare round on Codeforces on the 6th of June, with prizes and interesting (we will do our best:) ) problems. I invite everybody to take part in it, all the details will be in a separate topic.

Have a good day,
Looksery Inc

Today I came across this article, in which "Peter Norvig said that one thing that was surprising to him was that being a winner at programming contests was a negative factor for performing well on the job".

Normally I don't care about these topics, but this is from Google — where they have good population of high rated competitive programmers and the claim is backed with data.

The article mentioned one point: "programming contest winners are used to cranking solutions out fast and that you performed better at the job if you were more reflective and went slowly and made sure things were right". Though I don't think this is true. For example, being competitive programmer taught me:

1. bugs can be everywhere & we must code carefully
2. many problems have amazing solutions, and it's not a good idea to start coding anything that comes to mind.

Some comments talked about how competitive programmers write unmaintainable code or appear arrogant. Having lots of friends who are competitive programmers and read lots of comments here, I believe that these are also not the case.

• Yes, amongst rude comments made on Codeforces, many are from reds, but many are also from yellows, purples, blues, greens... and I think majority of high rated people here are very reasonable & nice.
• I think most people have some moments when we come back to read our old code writen in contests, and have no idea what we did. Since we've been there, it's not natural to think that we would write such code when we know that we need to maintain them.

I understand that the points I made above are probably biased. So what do you think? Do you believe that being good competitive programmer correlates negatively with being good on the job?

Hello, Codeforces!

The problems were suggested by users roosephu and Sunayuki. The great help in preparing was provided by Aksenov239, GlebsHP and Codeforces team. ZeptoLab Team did its best while working on statements.

The round will use smoother dynamic problem scores with 250 points steps.

In 2014 we hosted our first programming contest together with Codeforces, and we liked it!

Let me shortly remind you how it was. The contest consisted of 6 problems, 2.5 hours were given to solve (you can have a look at the problems of the previous year and try to solve them here).

Of course, even on a purely coding event we stayed true to ourselves, so all problems were designed based on our games, and, of course, we illustrated them with care:

Zepto Code Rush 2014 broke the existing Codeforces record of round popularity. Also we were glad to read a positive feedback about problems. By the way, the first three places were taken by developers from Russia. Some of them even came to pick up the prizes at the office, where they had a mini-tour and the highlight of the program: of course, the game in a giant Cut The Rope and our standard corporate "going green" welcome kit at the entrance (we call "going green" a welcome kit, full of fun gizmos of our corporate green color).

Hello everyone!

Congratulations from AIM Fund to Codeforces on their 5th anniversary! Many of our employees take part in competitive programming, so we took the opportunity to support the crowdfunding campaign run by Codeforces. We appreciate what we have learned here and we are grateful for the enjoyable moments that we spent solving interesting problems. Within the next month, we are planning to run our round and will do our best to create challenging problems.

Our company specialises in proprietary trading, the key concepts in our work are big data, low latency and high frequency. Our team mainly consists of graduates from the MSU Faculty of Mechanics and Mathematics and Moscow Institute of Physics and Technology (MIPT).