Codeforces and Polygon may be unavailable from February 22, 6:30 (UTC) to February 22, 20:30 (UTC) due to technical maintenance. Γ—

By KAN, 2 weeks ago, translation, In English

Hi Codeforces!

I have a great announcement for you. This month, we're holding the second Codeforces Blitz Cup! Remember all the WA1s and CEs we've seen from LGMs stressing out to submit before the opponent? They are coming back!

The Codeforces Blitz Cup is a single-elimination personal tournament where matches follow the special Blitz Rules. In short, each match is a 40-minute PvP contest, where problems open one by one, and only the first AC counts. The players can't use any help or prewritten code except a small template, and we get to watch them think and code live.

Check out last year's final rounds streams: day 1, and the final day 2 to get the feel for the format.

  • Eligibility: Grandmasters or above
  • Registration deadline: February 12, 10:00 UTC
  • Elimination rounds: February 13th to 26th (free schedule)
  • Live finals: February 28 to March 1 (online)
REGISTER

See you blitzing!

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By chromate00, 5 days ago, In English

Oh hello there. I, chromate00, am back! Oh no, I hope you are not misunderstanding me, I'm not pulling a joke on the announcement this time. I'm too busy for that right now. So here's the (mostly copy-pasted) announcement of Codeforces Round 1080 (Div. 3).

Anyways. Starting from Sunday, February 15, 2026 at 14:45UTC, you will be given 7 or 8 problems to be solved in 2.5 hours.

The round will be hosted by rules of educational rounds (extended ICPC). Thus, all solutions will be judged on preliminary tests during the round, and after the round, there will be a 12-hour phase of open hacks. After the open hack phase, all accepted solutions will be rejudged on successful hacks. Also, note that there is no score distribution but the usual penalty of 10 minutes for each wrong submission, following the rules of educational rounds.

Remind yourself that only the trusted participants of the third division will be included in the official standings table. As it is written by link, this is a compulsory measure for combating unsporting behavior. To qualify as a trusted participant of the third division, you must:

  • take part in at least five rated rounds (and solve at least one problem in each of them)
  • not have a rating of 1900 or higher at any moment in time.

Regardless of whether you are a trusted participant of the third division or not, if your rating is less than 1600, then the round will be rated for you (unless you register unrated).

Also, note the rule restricting the use of AI. If you are caught while breaking this rule, you will be sent to cry's new basement on Mars without oxygen.

This round is made possible by the help of the following people:

I hope that you will enjoy the contest. Good luck and have fun!

UPD1: Editorial has been posted

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By ConstructorU, history, 2 weeks ago, In English

Greetings Codeforces community!

CU

We are excited to announce the Constructor Open Cup 2026, our annual online programming competition organized by Constructor University and JetBrains Foundation.

What is the Constructor Open Cup?

Constructor Open Cup is an online contest organized by Constructor University and JetBrains Foundation to promote interest in computer science, data science, software development, and software engineering.

Put your knowledge and skills to the test in this 4-hour competition and stand a chance to walk away with a scholarship for a bachelor's degree in Software, Data and Technology (BSc SDT) at Constructor University, Germany’s #1 private university*!

Constructor Open Cup timetable

February 2 β€” February 12, 2026 | Practice Round

Get familiar with the testing environment during this practice round.

February 12, 2026 at 2 PM (UTC) | Main Round

You will have 4 hours to complete a series of algorithmic programming tasks. Registration closes 1 hour before the start of the contest.

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By FelixArg, 10 days ago, translation, In English

Hello, Codeforces!

sevlll777 and I are glad to invite you to participate in Codeforces Round 1079 (Div. 1) and Codeforces Round 1079 (Div. 2). Both rounds will take place at Wednesday, February 11, 2026 at 14:35UTC. There will be 6 problems in each round, some of them can be divided into several subtasks. You will have 3 hours to solve all the problems. The round will be held according to the Codeforces rules and will be rated for both divisions.

At least one problem will be interactive, so we highly recommend to read guide for interactive problems before the contest.

We would like to thank:

UPD 1: The score distribution is as follows:

  • Div. 1: 500βˆ’750βˆ’(750+750)βˆ’2250βˆ’(2000+1000)βˆ’3500
  • Div. 2: 500βˆ’1000βˆ’1250βˆ’1500βˆ’(1500+1500)βˆ’4000

UPD 2: Editorial

Wishing everyone good luck and high ratings!

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By TheEvilBird, 12 days ago, translation, In English

Hello, Codeforces!

This Sunday there will be a Moscow Olympiad for Young Students. This contest is prepared by Moscow Olympiad Scientific Committee that you may know by Moscow Open Olympiad, Moscow Team Olympiad, Metropolises Olympiad and All-Russian olympiad in the name of Keldysh.

We are glad to invite you to Codeforces Round 1078 (Div. 2) based on the problems of this olympiad, which will take place on Sunday, February 8, 2026 at 09:05UTC. Note the unusual time of the round. The round will be held according to the Codeforces rules and will be rated for all participants with rating below 2100.

Problems of this competition were prepared by silvvasil, Semen07, allvik66, dope, teraqqq guided by TheEvilBird, grphil and Helen Andreeva.

Thanks to FairyWinx for the round coordination, and also thanks for MikeMirzayanov ΠΈ KAN for Codeforces and Polygon platforms, which was used to prepare problems of this olympiad.

We also thank:

The scoring will be available later.

UPD: Scoring distribution: 500 β€” 1000 β€” 1750 β€” 2000 β€” 2500 β€” (1750 + 1750)

UPD: Since the round is based on an onsite olympiad, viewing other participants' submissions and upsolving will be available starting from 12:00 UTC

UPD: Until 13:00 UTC due technical reason

UPD: Editorial

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By -firefly-, 3 weeks ago, In English

Hello, Codeforces!

After years of hard work, we are euphoric to invite you to participate in Codeforces Round 1077 (Div. 1) and Codeforces Round 1077 (Div. 2), which will be held at Thursday, January 29, 2026 at 14:35UTC. For both divisions, you will be given 7 problems and 3 hours to solve them. For at least one of the divisions, one of the problems will be divided into two subtasks.

The problems are invented and prepared by Bronya_H, Error_Yuan, StarSilk, Tobo, __baozii__ and me.

We would like to thank:

The score distribution is below.

Div. 1: 750βˆ’1250βˆ’1750βˆ’2000βˆ’2250βˆ’(2000+3500)βˆ’3000.

Div. 2: 500βˆ’1000βˆ’1500βˆ’2000βˆ’2500βˆ’2750βˆ’3000.

We sincerely hope you can enjoy the problems. Good luck and see you on the field !

Bonus

UPD1: The hacks are disabled for problems A-D in Div 2, and for problems A-B in Div 1. We have final tests consisting of pretests and hacks for all problems.

UPD2: Editorial

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

Hello, Codeforces!

We are glad and excited to invite you to take part in Codeforces Round 1076 (Div. 3), which will take place on Sunday, January 25, 2026 at 14:35UTC. You will be given 2 hours and 15 minutes to solve 7-8 probmles. At least one problem will be interactive, so we highly recommend to read guide for interactive problems before the contest.

The round will be hosted by the rules of educational rounds (extended ICPC). Thus, all solutions will be judged on preliminary tests during the round, and after the round, there will be a 12-hour phase of open hacks. After the open hack phase, all accepted solutions will be rejudged on successful hacks.

As a reminder, only trusted participants of the third division will be included in the official standings table. This is a compulsory measure for combating unsporting behavior. To qualify as a trusted participant of the third division, you must:

  • take part in (and solve at least one problem in) at least five rated rounds
  • and not have had a rating of 1900 or higher at any moment in time.

Regardless of whether you are a trusted participant of the third division or not, if your rating is less than 1600, then the round will be rated for you (unless you register unrated).

Problems were authored by KluydQ, YF_YUSUF, Wansur, Mendeke.

We would like to give special thanks to:

UPD: Editorial is here

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By Fakewave, history, 4 weeks ago, In English

Hello, Codeforces!

We are excited and pleased to announce that Codeforces Round 1075 (Div. 2) will be held on Friday, January 23, 2026 at 14:35UTC. This round will be rated for all participants with rating below 2100. You will be given 2 hours to solve 6 problems and some problems will be divided into subtasks.

The round is based on the Sharygin International Geometry Olympiad All problems were authored and prepared by yanb0, furt1ve and me.

We would like to express our special thanks to:

The score distribution is below.

500βˆ’1000βˆ’(1250+750)βˆ’(2000+750)βˆ’2500βˆ’3250

GLHF!

UPD1 The round is over, thank you for participation.

UPD2 Editorial

UPD3 Winners and First to solve

Div2

Place Participant
1 Timmyliuyunxi
2 mainkkk
3 Suzt_ilymtics
4 RaresPoinaru
5 bookpig

Div1 + Div2

Place Participant
1 StarSilk
2 Rubikun
3 ksun48
4 potato167
5 kotatsugame

First to solve

Task Participant
A i_hate_pahadans
B 300iq
C1 thaibao08
C2 Codfish
D1 porzlck
D2 YuukiS
E Baskot
F GoatMessi30

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