By niyaznigmatul, 25 hours ago, translation, In English,

Hi, Codeforces!

Codeforces Round #402 (Div. 1) and Codeforces Round #402 (Div. 2) are going to happen on February, 26th, at 08:05 AM UTC. The round will run at the same time with Innopolis University Open, Olympiad in Informatics. Division 1 problems are the same as olympiad problems. Some of Division 2 problems are prepared by MikeMirzayanov, thanks to him.

The problems are developed by MikeMirzayanov, YakutovDmitriy, VArtem, firezi, burakov28, pashka.

We hope you enjoy the problems!

problem scores for div1: 500 — 1000 — 1500 — 2250 — 2250
problem scores for div2: 500 — 1000 — 1000 — 1500 — 2000 — 2500

UPD 2: Congratulations to winners!

Top-10 (Div.1)

  1. bmerry
  2. ainta
  3. Marcin_smu
  4. kcm1700
  5. moejy0viiiiiv
  6. anta
  7. FizzyDavid
  8. Reyna
  9. dotorya
  10. gs12117

Top-10 (Div.2)

  1. Chiaki.Hoshinomori
  2. WhyamIhere
  3. mjkocijan
  4. Schemtschik
  5. kiiiiii
  6. pisos_pro
  7. marcospqf
  8. fushar
  9. safarisoul
  10. Panole233

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By GlebsHP, history, 3 days ago, translation, In English,

Hello everybody!

Tomorrow round will be held using problemset of Moscow programming competition for school students of grades from 6 to 9. Do not be tricked by the age range of the participants, Moscow jury always tries its best to select interesting problems of various topics. Problems were developed by feldsherov, ch_egor,, ipavlov and GlebsHP.

Hope to see you in the standings!

P.S. Scoring distribution is standard.

UPD Congratulations to the winners!

  1. Mr.Stream

  2. mamka

  3. funtik


  5. XLightDog

UPD2 Problem analysis is here.

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By dark_n8, 4 days ago, In English,

Hello, Codeforces!

I would like to invite you all to the International Coding Marathon 2017, under the banner of Technex'17, which will take place on Thursday 23rd February 2017, 20:05 IST. The contest will be held as a combined Div.1+Div.2 round which will be rated for participants from both divisions. The prizes for the event have been sponsored by D. E. Shaw & Co..

The Indian Institute of Technology (BHU) Varanasi, India is proud to present the 78th edition of its widely renowned techno-management festival, Technex'17, to be held from 24th to 26th February 2017. Offering a myriad of diverse events across fields such as programming, robotics, and aero-modelling, it witnesses enthusiastic participation from all across India and abroad.

The problemset has been prepared by me(dark_n8), vikhs_96, Prateek1996 and ishank011. We would like to express our heartiest thanks to KAN for his constant help in preparing the contest and MikeMirzayanov for the amazing Codeforces and Polygon platforms. We also thank ashmelev and winger for their invaluable help in testing the problems.

UPD1: The start time of the contest has been delayed by 10 minutes.

UPD2: The scoring is 500-1000-1500-2000-2250-3000-3250.

UPD3: Thanks to all those who participated and heartiest congratulations to all the winners. The winners, who are eligible for prizes, will soon be contacted regarding the same.

Overall top 10:
1. ainta
2. tourist
3. LHiC
4. halyavin
5. jcccccccccccccccccccccsb
6. mnbvmar
7. uwi
8. moejy0viiiiiv
9. TakanashiRikka
10. Radewoosh

Indian top 5:
1. rajat1603
2. tanujkhattar
3. akulsareen
4. sampriti
5. PrashantM

Some of the problems were not up to the expectations. There were some issues with the site too. We deeply regret the inconvenience caused.

UPD4: The editorial for the round has been uploaded.


Prizes worth INR 100,000 up for grabs!

Overall 1st place: INR 35,000. Overall 2nd place: INR 25,000. Overall 3rd place: INR 15,000.

1st place in India: INR 10,000. 2nd place in India: INR 6,000. 3rd place in India: INR 4,000.

1st place in IIT (BHU) Varanasi: INR 4,000. 1st place among IIT (BHU) Varanasi freshmen: INR 1,000

Participants will have 2 hours to solve 7 problems. The scoring distribution will be announced soon.

Good luck everyone! Hope to see you on the leaderboard.

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By sidprasad, 8 days ago, In English,

Hi Codeforces!

Programming Club, IIT Indore and Fluxus 2017 are proud to present, for the first time on Codeforces, our flagship event, Divide By Zero!

The contest is going to be held on Monday, 20th Feb at 9:35PM IST.

Prizes: Codeforces T-shirts for top 15 overall and top 15 in India.

Thanks to the following people for making this round possible:

There are 7 problems, and 2.5 hours to solve them. The points distribution will be updated later.

Fluxus is the annual techno-cultural festival of Indian Institute of Technology, Indore. It is a 3-day event and generally held in the month of February. Started in 2011, Fluxus is the largest college festival of central India.

Hope you guys enjoy the contest! See you on the leaderboard!

UPD: The scoring is 500-1000-1250-1750-2000-2250-2750.

UPD2: Thanks a lot everyone for your participation!

We hope you all enjoyed the contest. Yes, there were a few things we could've done better, and unfortunately the system was down for a while, We sincerely thank the CF team for dealing with it in the nick of time.

This was our first (of many, hopefully) contest on Codeforces. We request you to fill in this form with your feedback so that we can do better next time. Thank you!

The following users win T-shirts! Congrats!

Overall Top 15:

  1. y0105w49
  2. W4yneb0t
  3. V--o_o--V
  4. Merkurev
  5. anta
  6. I_love_Tanya_Romanova
  7. Endagorion
  8. BigBag
  9. cubelover
  10. moejy0viiiiiv
  11. natsugiri
  12. mnbvmar
  13. halyavin
  14. Shik
  15. TheLightning

Indian Top 15:

  1. Sumeet.Varma
  2. rajat1603
  3. xorfire
  4. memset123
  5. rekt_n00b
  6. akulsareen
  7. shubham1694
  8. alecsyde
  9. AnonymousBunny
  10. ajinkya1p3
  11. mohitbindal
  12. wittyskull
  13. ramesh.aggarwal
  14. ajs97
  15. polingy

UPD3: Editorial

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By KAN, 10 days ago, In English,


The Codeforces Round #398 (Div. 2) is going to be held on Saturday, 18 February 2017 at 9:05 UTC for participants from division 2.

The round is based on XIII Nizhny Novgorod Olympiad in Informatics for high school students named after V. D. Lelyukh, which will take place on Saturday in Nizhny Novgorod. However, not all problems from the Olympiad are included into this round.

The problems were prepared by KAP, ashmelev, ZhNV, kuzmichev_dima, mmatrosov, mike_live, arsor and me.

You will be given two hours to solve five problems. As usual, participants from division 1 can take part out of competition.

Scoring: 500-1250-1500-2000-2500.

UPD: The contest is over, thanks to all who has participated! Congratulations to the winners:

Div. 2:

  1. maryanna2015
  2. imperishableshooting
  3. aquatic
  4. Cth1999
  5. mister_dudec
  6. FallDream
  7. Illidan
  8. Alex342
  9. A.Magdy7 and TmEnd

Div. 1:

  1. eddy1021
  2. HellKitsune
  3. I_love_Tanya_Romanova
  4. gritukan
  5. latte0119

I apologise for the problem difficulty of the problem B, we expected much more accepteds. Hope you liked the problems! The editorial will be posted in 1.5 hours after the Olympiad is finished. Editorial.

We know about the issue with ratings, they will be rolled back and then updated properly. Don't worry.

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By KAN, 13 days ago, In English,

Hi Codeforces!

The Codeforces Round #397 by Kaspersky Lab and Barcelona Bootcamp (Div. 1 + Div. 2 combined) is going to be held tomorrow at 8:05 UTC!

This round is organized in collaboration with Hello Barcelona ACM ICPC Bootcamp 2017 and supported by Kaspersky Lab.

Over 100 students from 17 countries and more than 25 universities such as Cornell University, University College London, École Normale Supérieure, University of Tokyo, Saint-Petersburg State University and Moscow Institute of Physics and Technology gathered in Barcelona to train together for the ACM ICPC Finals.

For eight days students have been solving problems, listening to lectures, learning and making new friends. The training schedule is intense consisting of full-length practice contests, interleaved with one-day educational modules on topics we find especially important. Every contest is followed by an in-depth explanations of every problem and technique encountered in all forms.

It is hard to convey the atmosphere of the event in words. It is said, a picture is worth a thousand words and here is a selection to give you some idea of this fantastic bootcamp. You can see more pictures from the event here and here.

The round authors are Endagorion, ifsmirnov, zemen and Arterm. The round is combined for both divisions, will contain seven problems and last for three hours. Good luck!

UPD: The scoring is 500-1000-1250-2000-2500-3250-3500.

The contest is finished. We hope that you enjoyed it. Congratulations to the winners!

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By mahmoudbadawy, history, 3 weeks ago, In English,

Hello Codeforces!

I'm glad to announce that on Feb/07/2017 17:05 UTC Codeforces Round #396 for the second division will take place. As usual, First division participants can take part out of competition.

This round was prepared by me and mohammedehab2002.

I'd like to thank moaz123 for helping us prepare the round, zoooma13 for testing some problems, KAN for helping us in contest preparation and for translating the statements into Russian and MikeMirzayanov for the great Codeforces and Polygon platforms.

You will be given 5 problems and 2 hours to solve them.

The scoring distribution will be announced later.

UPD 500-1000-1500-2000-2500

UPD editorial is ready

UPD Congratulations to the winners!


  1. Verstand

  2. sd0061

  3. rajat1603

  4. gritukan

  5. ulna


  1. Verstand

  2. zhfs_ga_pitona

  3. zelta

  4. AomeII

  5. bciobanu

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By platypus179, history, 4 weeks ago, translation, In English,

Ladies and gentlemen!

Codeforces Round #395 for both divisions will happen tomorrow, on Thursday, 2 February 2017 at 13:35 UTC.

Problems were prepared by me (Vasiliy Alferov) and students of Moscow school #179: s17b2_voroneckij (Dima Voronetsky), ilya_the_lamer (Ilya Pauzner) and akvasha (Anton Kvasha). Also, KAN (Nikolay Kalinin) is author of one of the problems.

Invaluable help was given to us by Codeforces coordinator KAN (Nikolay Kalinin). Thanks to MikeMirzayanov (Mike Mirzayanov) for wonderful platforms Codeforces and Polygon. Also thanks to Endagorion (Mikhail Tikhomirov), winger (Vladislav Isenbaev), AlexFetisov (Alex Fetisov) and cdkrot (Dmitry Sayutin) for reading out our statements and testing the round.

Participants will be given five problems in both divisions. Some of the problems will be common for both divisions. The scoring distribution will be announced later.

Good luck to all!

UPD: Scoring distribution:

Div1: 500-750-1500-2000-2500

Div2: 500-1000-1500-1750-2500

UPD2: The contest is over. Hope you enjoyed the problems :)

UPD3: Congratulations to the winners!

Div 1:

  1. moejy0viiiiiv

  2. V--o_o--V

  3. fjzzq2002

  4. SkyDec

  5. uwi

  6. Belonogov

  7. aid

  8. dreamoon

  9. Um_nik

  10. Andrei1998

and Div 2:

  1. ljh2000

  2. MashiroSky

  3. sqcszboyi

  4. _Reborn_

  5. Factorio

  6. Dirak

  7. lnjlnj

  8. Manchery

  9. SarvagyaAgarwal

  10. mik

The editorial will be posted very soon.

UPD5: Editorial

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By Vladik, 4 weeks ago, translation, In English,

Hi there!

Codeforces round #394 for the second division will take place at the time of Tuesday, 31 January 17:35 MSK. Participants from the first division can compete out of competition. Contestants will have 2 hours and 6 problems to solve.

  • Problems were developed by me (Vladislav Vishnevki) and Denis Anischenko (altruist).
  • Alexey Vistyazh (netman) helped us as a contest coordinator.
  • Aliaksandr Drapko (sdryapko) and Alena Yaros were reading the statements carefully.
  • Vlad Khala (hapooo) tested the round.
  • Olya Yakovchik drew amazing illustrations for the problems.
  • Yuri Shilyaev (hloya_ygrt) translated editorials and round announcement for you.
  • And of course the round couldn't happen without (MikeMirzayanov), the author of platform polygon and codeforces, and also author of the idea to one of our problems.

Thanks everyone listed for the contribution you made to the contest preparation!

The main character of the legends is tiger Dasha, which loves to solve puzzles and make origami figures.

Good luck everyone! :)

UPD Round will consist of 6 problems.

UPD 500-1000-1500-2000-2500-3000

UPD Contest finished. It was decided to make round unrated, because codeforces is unstable now. I am really sad about that :( I hope everyone found a problem he liked. Editorial will be posted soon.

UPD Top 10 participants from second division: 1. mitterr
2. wh2000
3. Inhibitor
4. Border_Collie
5. HanwhaEagles
6. Vergara
7. zelta
8. GGOSinon
9. X-tazy
10. tonykky

Top 10 participants from first division: 1. eddy1021
2. Myungwoo
3. dreamoon
4. natsugiri
5. Shik

Congratulations to the winners!

UPD Editorial.

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