Hello! Codeforces Round 776 (Div. 3) will start at Mar/08/2022 17:35 (Moscow time). You will be offered 7-8 problems with expected difficulties to compose an interesting competition for participants with ratings up to 1600. However, all of you who wish to take part and have a rating of 1600 or higher, can register for the round unofficially.

The round will be hosted by rules of educational rounds (extended ACM-ICPC). Thus, solutions will be judged on preliminary tests during the round, and after the round, it will be a 12-hour phase of open hacks.

You will be given 7-8 problems and 2 hours and 15 minutes to solve them.

Note that the penalty for the wrong submission in this round (and the following Div. 3 rounds) is 10 minutes.

Remember 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), do not have a point of 1900 or higher in the rating. 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.

Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of our work. Problems have been created and written by ITMO University teams: MikeMirzayanov, MisterGu, myav, Gol_D, Aris, senjougaharin, me Vladosiya.

Also many thanks to mango_lassi, espr1t, karemo, starboy_jb, Fly_37, omikad, Katya_Goryachkina, Omja, teraqqq, oversolver, Jostic11, yorky, _4dr_ and doreshnikov for testing the contest and valuable feedback.

Good luck!

UPD: Congratulations girls on International Women's Day <3.

UPD 2: Editorial

Hello!

Right now happens the first tour of the Open Olympiad in Informatics, and tomorrow will be the second one. This contest is prepared by Moscow Olympiad Scientific Committee that you may know by Moscow Team Olympiad, Moscow Olympiad for Young Students and Metropolises Olympiad (rounds 327, 342, 345, 376, 401, 433, 441, 466, 469, 507, 516, 541, 545, 567, 583, 594, 622, 626, 657, 680, 704, 707, 727, 751).

Open Olympiad consists of the most interesting and hard problems that are proposed by a wide community of authors, so we decided to conduct a Codeforces regular round based on it, which will happen on Mar/06/2022 12:55 (Moscow time) and will be based on both days of the Olympiad. Each division will have 6 problems and 2 hours to solve them.

We kindly ask all the community members that are going to participate in the competition to show sportsmanship by not trying to cheat in any manner, in particular, by trying to figure out problem statements from the onsite participants. If you end up knowing some of the problems of Moscow Open Olympiad (by participating in it, from some of the onsite contestants or in any other way), please do not participate in the round. We also ask onsite contestants to not discuss problems in public. Failure to comply with any of the rules above may result in a disqualification.

Problems of this competition were prepared by cookiedoth, shishyando, gmusya, Tikhon228, ligaydima, Siberian, isaf27, I_love_myself, talant, KiKoS, _overrated_ guided by cdkrot, vintage_Vlad_Makeev, GlebsHP, Zlobober, meshanya, ch_egor, grphil, voidmax, fedoseev.timofey, Endagorion and Helen Andreeva.

Thanks to gop2024 and KAN for the round coordination, statement translation and preparation of problems for the second division, and also thanks for MikeMirzayanov for systems Codeforces and Polygon, which was used to prepare problems of this olympiad.

Also thanks to low_ and Jeffrey for providing an additional problems that helped to create (I hope) a balanced problem set for the round.

Good luck everybody!

Due to the official competition source codes of other participants will not be available for an hour after the end of the round.

UPD1: Winners!

Div. 1:

1. jiangly
2. QuietBeautifulThoughts
3. maroonrk
4. 137_345_2814
5. Elegia

Div. 2:

1. AC464
2. Nephry
3. andyzys
4. Let_Us_Rebegin
5. _JacderZhang_

UPD2: Editorial

Hola Codeforces!

I am happy to invite you to Codeforces Round 774 (Div. 2), which will take place on 04.03.2022 18:35 (Московское время). Notice the unusual time! The round will be rated for participants with rating lower than 2100. You will have 2 hours to solve 6 problems. The problems were authored and prepared by me.

I would like to thank the following people who made the round possible:

• darkkcyan for coordination and help in problem preparation.
• KAN for translating the statements.
• antontrygubO_o, errorgorn, mjhun, wxhtzdy, generic_placeholder_name, Supermagzzz, vinfat, fishy15, phattd, MarcosK, TeaTime, Stepavly, SebaMarin, CarusoX, snowysecret, ak2006, DeMen100ns and helcsnewsxd for testing and providing valuable feedback.
• MikeMirzayanov for great Codeforces and Polygon platforms.

See you in the standings!

UPD:

Scoring distribution: $$$750$$$ — $$$1000$$$ — $$$1250$$$ — $$$2000$$$ — $$$2500$$$ — $$$3000$$$

Thanks to ak2006, video editorials for some of the problems will be available on his channel after the round.

UPD: Editorial

UPD: Congratulations to the winners!

Official winners:

1. lydia1
2. mjhmjh1104
3. Turret
4. Vsinger_MoQingxian
5. WAduck
6. woolim
7. Iam1789
8. yagoo
9. Koba.rde
10. dtc03012

Unofficial winners:

1. Vercingetorix
2. Um_nik
3. hank55663
4. Umi
5. dlalswp25
6. disorientation
7. rainboy

Hello, Codeforces.

In this post, I'll share with you a few recent improvements in Polygon made by MikeMirzayanov, unreal.eugene, DK318 and me.

Polygon is a service to prepares programming problems and contests. It is usually used to prepare problems for olympiads/programming contests but it is also often used to prepare educational content. It is located at https://polygon.codeforces.com/ and is open to everybody.

Here are three recent new features:

• IOI-like Graders for Python
• Problem Materials
• User Groups

Hi Codeforces,

I am honored to present you "Adolescent Grigore Moisil" (AGM) International Programming Contest (8th edition).

AGM is addressed to high school students who can form teams of up to 3 members, ICPC style. The contest has a qualification round on 6th March 2022 at 13:00 GMT. The problems are set up fully by (former) university students.

We are looking forward to international participants. Both the qualification and final round will be held online due to the pandemic situation. You can register here until 5th March 2022 at 13:00 GMT.

Besides diplomas for the first 10 teams in the final round, the first team will receive a prize of 1200 RON, the second team a prize of 900 RON, and the third team a prize of 600 RON.

Finally, I am more than delighted to present you our team: patrick.sava (the heart of the project), average_frog_enjoyer, munteanuvlad98, Stelutzu, Alex18mai, teoionescu, carabet.cosmin, Stefan_Radu, Mihai22e, vreaudelftpls, GinguIonut, caesar2001, georgerapeanu, MiricaMatei, popovicirobert, tinca_matei, Usu and me.

Take a look at our problem-sets from the last edition:

Qualification

Final Round Day1

Final Round Day2

Our website

AGM Facebook

Registration Link

Also, don't hesitate to contact us: [email protected]

Thank you very much,

George

Given the current circumstances, we have decided to postpone Kotlin Heroes until further notice. Thank you for your understanding.

Hello, Codeforces!

First and foremost, we would like to say a massive thank you to everyone who entered and submitted their answers to the eight Kotlin Heroes competitions which were held previously: Episode 1, Episode 2, Episode 3, Episode 4, Episode 5: ICPC Round, Episode 6, Episode 7, and Episode 8.

Ready to challenge yourself to do better? The [contest:1643] competition will be hosted on the Codeforces platform on [contest_time:1643]. The contest will last 2 hours 30 minutes and will feature a set of problems from simple ones, designed to be solvable by anyone, to hard ones, to make it interesting for seasoned competitive programmers.

Prizes:

Top three winners will get prizes of $512, $256, and $128 respectively, top 50 will win a Kotlin Heroes t-shirt and an exclusive Kotlin sticker, competitors solving at least one problem will enter into a draw for one of 50 Kotlin Heroes t-shirts.

Registration is already open and available via the link. It will be available until the end of the round.

The round will again be held in accordance with a set of slightly modified ICPC rules:

• The round is unrated.
• The contest will have 9 or 10 problems of various levels of complexity.
• You are only allowed to use Kotlin to solve these problems.
• Participants are ranked according to the number of correctly solved problems. Ties are resolved based on the lowest total penalty time for all problems, which is computed as follows. For each solved problem, a penalty is set to the submission time of that problem (the time since the start of the contest). An extra penalty of 10 minutes is added for each failed submission on solved problems (i. e., if you never solve the problem, you will not be penalized for trying that problem). If two participants solved the same number of problems and scored the same penalty, then those of them who had previously made the last successful submission will be given an advantage in the distribution of prizes and gifts.

If you are still new to Kotlin we have prepared a tutorial on competitive programming in Kotlin and [contest:1645], where you can try to solve a few simple problems in Kotlin. The practice round is available by the link.

We made an announcement about the Kotlin Heroes: Episode 9 practice stream, but unfortunately we had to cancel it. Sorry for the inconvenience!

We wish you luck and hope you enjoy Kotlin.

Hello, Codeforces!

We are glad to invite everyone to participate in Codeforces Round 773 (Div. 1) and Codeforces Round 773 (Div. 2), which will be held on Feb/23/2022 13:10 (Moscow time). Notice the unusual time! The round will be rated for both divisions. Each division will have 6 problems, and you will have 2 hours to solve them. We recommend you read all the problems!

Tasks are based on RocketOlymp, and were written and prepared by __silaedr__, daubi, alegsandyr, ilyakrasnovv, and isaf27.

We are very thankful to

• isaf27 for the great coordination, valuable advice, and patience.

• Renatyss, stepanov.aa, talant, Siberian, kirill.kligunov, arbuzick for the help during discussing and preparing problems.

• Our testers: AlperenT, ArtNext, EvgeniyPonasenkov, FedShat, Qwerty1232, TeaTime, TheEvilBird, ak2006, generic_placeholder_name, philmol, silvvasil, tox1c_kid for their feedback

• pakhomovee for the task, that didn't find its place in the final problemset.

• KAN for helping with round preparation

• MikeMirzayanov for codeforces and polygon platform

Olympiad's participants cannot participate in codeforces rounds simultaneously.

Good luck and have fun!

UPD — Scoring distribution:

div2: $$$500 - 750 - 1250 - 2000 - 2000 - 2500$$$

div1: $$$500 - 1250 - 1250 - 1750 - 2250 - 3000$$$

UPD — Editorial

Hello Codeforces!

On 22.02.2022 17:35 (Московское время) Educational Codeforces Round 123 (рейтинговый для Div. 2) will start.

Series of Educational Rounds continue being held as Harbour.Space University initiative! You can read the details about the cooperation between Harbour.Space University and Codeforces in the blog post.

This round will be rated for the participants with rating lower than 2100. It will be held on extended ICPC rules. The penalty for each incorrect submission until the submission with a full solution is 10 minutes. After the end of the contest you will have 12 hours to hack any solution you want. You will have access to copy any solution and test it locally.

You will be given 6 or 7 problems and 2 hours to solve them.

The problems were invented and prepared by Adilbek adedalic Dalabaev, Vladimir vovuh Petrov, Ivan BledDest Androsov, Maksim Neon Mescheryakov and me. Also huge thanks to Mike MikeMirzayanov Mirzayanov for great systems Polygon and Codeforces.

Good luck to all the participants!

Our friends at Harbour.Space also have a message for you:

Hey, Codeforces!

Once again, it is time for another exciting scholarship opportunity from Harbour.Space!

We have partnered with various tech companies to offer Bachelor’s or Master’s degree scholarships in Computer Science, Data Science, Cyber Security, and Front-end Development and work experience in the partnered companies.

We are looking for various junior to mid-level positions to fill in different fields such as:

• Java Spring / Node.js Back-End Developer
• DevOps Engineer
• Kotlin Web App Developer
• React / React Native Front-End Developer
• Cyber Security Specialist

Requirements:

1. High School Diploma for Bachelor degree applicants or Bachelor’s degree for Master degree applicants
2. Professional fluency in English
3. Previous experience is a must for Master student applicants and a plus for Bachelor student applicants

Make sure to apply before Mar 13, 2022, to be eligible for the scholarship and reduced application fee.

Keep in touch and follow us on LinkedIn for more scholarship opportunities. And follow us on Instagram to evidence student life, events, and success stories from students.

Good luck on your round, and see you next time!

Harbour.Space University

UPD: Editorial is out

Hello, Codeforces!

dannyboy20031204 and I are glad to invite everyone to participate in Codeforces Round 772 (Div. 2), which will be held on 20.02.2022 17:35 (Московское время). This Round will be rated for participants with rating lower than 2100. You will have 2 hours to solve 6 problems.

We would like to thank:

• 74TrAkToR for excellent coordination of the round and translating the statements.
• 244mhq, generic_placeholder_name, null_awe, ptd, Fysty, 8e7, yungyao, Devil, amano_hina, Dragonado, DIvanCode, voventa, plagues, Marslai24, FHVirus, saarang, olyazyryanova, marzipan, Prokhor08, sam571128, efimovpaul, ColtenOuO, zarubin, sus for testing this round and providing very useful feedback.
• generic_placeholder_name for providing an awesome problem idea when our problems are rejected by the coordinator.
• 8e7 for verifying our statements and tutorials, correcting many mistakes and making it easier to read.
• MikeMirzayanov for great Codeforces and Polygon platforms.

Score distribution: $$$500 - 1000 - 1500 - 2250 - 2250 - 3000$$$

I hope all of you will enjoy the problems and have a positive delta. GL & HF ^^.

UPD1: Thanks for your participation! Editorial is out.

UPD2: Congratulations to the winners:

Div1 + Div2:

1. jqdai0815
2. eecs
3. MatikaneTannhauser
4. kotatsugame
5. risujiroh

Div2:

1. MatikaneTannhauser
2. disorientation
3. rainboy
4. Bekzhan
5. Vsinger_YuezhengLing