Good day, codeforces)

Welcome to regular Codeforces round #246 for Div.2 participants. As always Div.1 participants can take part out of the competition.

The problems were prepared by authors Pavel Kholkin (HolkinPV) and Gerald Agapov (Gerald). Is not the first and definitely not the last time when we tried our best for you. Traditionally thanks to Michael Mirzayanov (MikeMirzayanov) for perfect Codeforces and Polygon systems and Mary Belova (Delinur) for translating the problems.

UPD: Score distribution will be standard — 500-1000-1500-2000-2500.

UPD2: The contest is over, we hope you enjoy it)

UPD3: the editorial is here

Congratulations to winners!:

1) PopovkinAndrey
2) FTD2009
3) Gulan14no
4) Kozakai_Aya
5) Mikael

We wish all participants good luck and enjoyment of solving problems)

After a short delay (but Oscar is given in spring too, huh?) we are pleased to announce the Cormen Medal laureates for 2013. This year, we’ve decided to slightly upgrade nominations again, so this year's Cormen Medal is given in two nominations:

• Best Progress
• Best Problemsetter

Best Progress

The Cormen Medal laureate in this nomination is Scott Wu (scott_wu, USA). Note the sharp upward dive his rating line takes. His achievements in 2013 are not limited by the spectacular dive into the best 10 participants on Codeforces: he got the 5-th place on IOI, won the 2013 season of the USACO contests, got target on TopCoder! We congratulate Scott and wish him many more achievements!

Best Problemsetter

We didn't have to search far and wide for the winner in this nomination. Naturally, the Cormen Medal goes to the most productive and loved by many author of 2013, Sergey Nagin (Sereja, Ukraine). Sergey prepared and conducted 7 rounds (all of them Div1+Div2) on Codeforces. Sergey's problems gained popularity among the Codeforces coders and we will be happy to see his contests again in the future! Sergey has already been awarded by a Medal and an Award Plate in February in Kharkov training camp.

Looks like it's becoming a good tradition. The laureates will be sent a book by Thomas Cormen (Introduction to Algorithms or Algorithms Unlocked), signed by the author.

History

Let us remind you that the Cormen medals have been awarded for the fourth year. tourist (Gennady Korotkievich) became the best participant three years in a row (in all the years when this nomination existed). Alex_KPR (Alexander Kouprin) became the best blogger in both years when this nomination existed. My favourite nomination "Best Problemsetter" was awarded to: natalia (Natalia Bondarenko) in 2010, Ripatti (Artyom Ripatti) in 2011, and witua (Vitaly Gerasimov) in 2012. Besides, in 2012 there was a medal for "Codeforces Spirit of Community 2012", the laureate was Nickolas (Mariia Mykhailova).

Hello everyone!

We invite you to participate in Codeforces Round #245, scheduled for Sunday, 11th May at 7:30 MSK. This is the fourth round I write for Codeforces. After the last round your upvotes helped me get into the Contributors Top 10. Thanks for all your good remarks; I'll try and do my best in order for this round to be at least as good as the previous one.

This round is prepared by my friend Ioan Petcu (author of D1 E) and I (all problems, except D1 E). We've chosen the problems to be as diverse as possible — no two problems will share the same programming technique. As the problems are varied, we hope you'll find at least one problem of your taste. The main character is Iahub, currently the number one ranked contestant in the Romanian selection camps for IOI. After reading the problem statements, you'll see what the life of a very good Romanian competitive programmer is like (just kidding, it's just my evil imagination).

This round wouldn't have been possible without the people that helped me test it: Gerald Agapov (Gerald), Damian Straszak (DamianS), Dan Alexandru (DanAlex) and Vlad Badelita (vladb). As always, we’d like to thank Mike Mirzayanov for creating the Polygon system and Codeforces plaftorm and to Delinur for translating the problems in Russian.

We wish high ratings to everyone and, above all, have fun!

UPD Score Distribution

Division 1: 500 1000 1500 2000 2000

Division 2: 500 1000 1500 2000 2500

I apologize for all technical issues during the round, from the ambiguous problem statements to very easy problem D1 D. In my trial to invent a nice task, I didn't see that straight forward solution for it and I have no excuse for this.

UPD Winners

Division 1:

1. SergeyRogulenko
2. scott_wu
3. vepifanov
4. YuukaKazami
5. ballon

Division 2:

1. clavichord93
2. krmunn481
3. Dgleich
4. PopovkinAndrey
5. roben_76

UPD Editorial

UPD Statistics

Good day everyone.

Codeforces round #244 for division 2 participants will start at May 2, Friday, 19:30 MSK. As you all know, participants from division 1 can also take part from out of the competition.

The round was prepared by me (Bidhan), student of University of Dhaka, Bangladesh. This is my first codeforces round. I have tried to prepare interesting and solvable problems for division 2 participants. Special effort was given to make the problem statements as clear as possible. Hoping that everything will go right and everyone will enjoy the round.

Special thanks to msh_shiplu, lecturer of University of Dhaka, for his contribution to the contest by finding time to set one of the problems, writing alternates, reviewing problem statements and giving expert advice on dataset generation in spite of his hectic schedule.

Also, a BIG thanks to nice guy Gerald, for helping throughout the preparation process.

I wish all the participants good luck :)

Update0 : Score distribution is 500-1000-1500-2000-2500.

Update1 : A short editorial of the contest is here. The post will be enlarged to detailed editorial later.

The Russian translation of this post is here.

Hello everyone!

Codeforces Round #243 will take place on Sunday, April 27th at 19:30 MSK. This is my eleventh Codeforces round and I hope not the last.

I'd like to thank Gerald and KADR for helping me to prepare the round. Special thanks to Delinur for translation of all problem statements into English.

I strongly recommend you to read ALL the problems.

Problem point values in first division 500-1000-1500-2000-2000. In second division — standard.

Gl & hf ! :)

Tutorial.
Statistics.

Hi, everyone!

Regular Codeforces round #242 for participants from the second division will take place on 25 April, 11:00 MSK. Participants from the first division are able to participate out of the competition.

The contest is prepared by programmers from Tomsk Polytechnic University: Pavel Khaustov (pkhaustov), Olesya Golub (Taube), Nickolay Kuzivanov (Carups), Dmitry Savvinov (Dsavvinov), Alexey Vetrov (noxwell).

Special thanks to Vladimir Chalyshev (cmd) and Alexey Dergunov (dalex) for their impact.

Also, thanks to Codeforces team and, especially, to Gerald Agapov (Gerald) and Maria Belova (Delinur).

Points distribution: 500-1000-1500-2500-3000

Good luck!

Good evening!

The final contest of Coder-Strike 2014 will be started tomorrow at 16:00 MSK. The problems (as in previous Coder-Strike 2014 rounds) are prepared by: Gerald, HolkinPV, Igor_Kudryashov.

And we have good news for you. There are two rated online rounds related to the contest: one round for the first division participants and the other for the second division participants. Of course, we've added simple problems in the second division contest (and also deleted hard problems).

The registration for the contest will start at 4:00 MSK, as usual registration ends 5 minutes before the contest start. The first division participants should register on "Coder-Strike 2014 — Finals (online edition, Div. 1)", the second division participants should register on "Coder-Strike 2014 — Finals (online edition, Div. 2)".

Hope the problems will be nice for you, we are really tried our best to prepare them.

Good luck!

UPD. Due to the holding the onsite competition of Coder-Strike 2014, we have to restrict access to the site after the contest. Approximately, the site will be unavailable for 15-30 minutes after the end of the contest.

The editorial is now available.

Good day!

Coder-Strike 2014: Round 2 will start tomorrow at Russian morning. If you want to participate, please register for the contest on the page.

In much the same way as the first round, all users can take part in the competition. But this round will be usual rated round only for the second division participants. The first division participants can take part too, but for them the round will be unrated. Please, do not get upset, the next Coder-Strike round (finals) will be rated round for the first division participants.

If you have any additional questions, please, ask at comments.

Good luck, and see you on the contest!

UPD 1. Sorry for delay, the score distribution is standard.

UPD 2. The contest is over, congratulations to the winners, hope you like the problems!

Good Day!

Coder-Strike 2014: Round 1 will start very soon. If you want to participate, please register for the contest on page. The round was prepared by me, HolkinPV and Igor_Kudryashov. And we tried our best to make it really awesome.

The round will be usual rated round for the second division participants. The first division participants can take part too, but for them the round will be unrated.

If you have any additional questions, please, ask at comments.

Hope you enjoy the problems! Good luck!

UPD 1. Score distribution will be standard: 500-1000-1500-2000-2500.

UPD 2. The competition was delayed by 10 minutes. :]

UPD 3. Because of unusual room assignment Div.1 and Div.2 participants will be in the same rooms this round.

UPD 4. The contest has ended, hope you like the problems. Rating for Div.2 participants will be updated a bit later.