Registration for International Data Analysis Olympiad (IDAO 2021) is open now. It’s being organized by HSE University and Yandex for the 4th time. Otkritie bank will be our platinum partner this year. The Olympiad will be convened by leading experts in data analysis and aims to bring together analysts, scientists, professionals, and junior researchers. Participation is free. Winners and prize-winners of IDAO 2021 will receive valuable prizes.

This year the online task is coming again from Physics. The task was given by the Laboratory of Methods for Big Data Analysis (LAMBDA, HSE University) together with CYGNO Collaboration (Italy).

The registration is open till March 12, 2021. The Olympiad includes two stages:

Online Stage (March 1-31):

• Track 1: Traditional machine learning competition on Yandex.Contest platform. You will need to make new predictions and upload them to the automatic verification system.
• Track 2: Come up with a solution for the same problem, keeping within a rigid framework of time and memory used.

Final (April 17-18):

• top 30 teams according to the Online Stage results will be invited to the Online final.
• In the final 36 hours of the competition, participants will try not just to train the model, but to create a full-fledged prototype, which will be tested both in terms of accuracy and performance.

Learn more: https://idao.world/

Hi, Codeforces!

I finally get to return something to this great community, so I am glad to invite you to take part in Codeforces Round #703 (Div. 2), which will take place on Feb/18/2021 17:35 (Moscow time). The round will be rated for the participants with rating lower than 2100. Participants from the first division are also welcomed to take part out of competition.

You will be given 2 hours 15 minutes to solve 6 problems. All the problems were created and prepared by me. One of the problems is interactive, please read the guide of interactive problems before the contest.

I would also like to thank:

• antontrygubO_o for excellent coordination!
• Monogon, 3EVEHAR_KOAVA, Akulyat, Aleks5d, BRCode, Osama_Alkhodairy, PO3OBAR_Bblnb, arzhantsev64, bWayne, Aditya_Mittal_31, kassutta, kclee2172, kalki411, sdl for testing the round and giving valuable feedback.
• Aleks5d for proposing another solution to one of the problems.
• MikeMirzayanov for great Codeforces and Polygon platforms!

Scoring: $$$500-1000-(750+750)-1750-2250-3000$$$.

Don't forget to read ALL the problems. I wish you good luck and high ratings!

I tried my best to create some good problems and clear statements, so I hope you'll enjoy the round:)

UPD: Editorial

UPD: Winners and First to solve

Div1 + Div2

Div2

First to solve

For example, tourist, you can find it on his profile page:

Hello, Codeforces!

<almost-copy-pasted-part>

Hello! Codeforces Round #702 (Div. 3) will start at Feb/16/2021 17:35 (Moscow time). You will be offered 7 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 1600 or higher, can register for the round unofficially. The round will be hosted by rules of educational rounds (extended ICPC). Thus, during the round, solutions will be judged on preliminary tests, and after the round it will be a 12-hour phase of open hacks. I tried to make strong tests — just like you will be upset if many solutions fail after the contest is over.

You will be given 7 problems and 2 hours 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 trusted participants of the third division, you must:

• take part in at least two 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.

The problems for this round were invented by MikeMirzayanov, Supermagzzz, Stepavly and sodafago.

Thanks to MikeMirzayanov for platforms and coordination of our work. Thanks to darkkcyan, Sho, sodafago, budalnik, kocko, akagami_no_shanks, Gassa, infinitepro, bfs.07 for help in round preparation and testing the round.

Good luck!

</almost-copy-pasted-part>

UPD: Editorial is ready!

Hello Codeforces!

On Feb/15/2021 17:35 (Moscow time) Educational Codeforces Round 104 (Rated for 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 Roman Roms Glazov, 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:

Amazing news, Codeforces!

As we promised last time, we are coming back with a new scholarship opportunity!

We have partnered with Coherra to open the door for an exciting career in technology for the most talented people in our network.

In partnership with Coherra, we are offering a full scholarship to study a Master’s in Front End Development at Harbour.Space while working as a Front End Developer at Coherra!

Scholarship Highlights:

➡ Work in Europe’s most exciting tech cities

➡ Scholarship value of up to €22,900 to study at Harbour.Space University

➡ Competitive compensation for the internship at Coherra

➡ Opportunity to join Coherra full-time after graduation

We have previously partnered with other companies like OneRagtime, Hansgrohe, and Remy Robotics to empower young talents around the world and help them boost their tech career. We’ve already filled a few of the positions with our partners including:

• Full Stack Developer at OneRagtime awarded to Alejandro Martinez from Mexico
• Innovation Designer at Hansgrohe awarded to Giorgi Zhuzhiashvili from Georgia

We are always happy to see Codeforces members join the Harbour.Space family. Apply now to get a chance to learn from the best in the field and kickstart your career!

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 our apprenticeship programme students.

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

Harbour.Space University

Congratulations to the winners:

90 successful hacks and 1286 unsuccessful hacks were made in total!

And finally people who were the first to solve each problem:

UPD: Editorial is out

Ciao, Codeforces! We're glad to invite you to take part in Codeforces Round 701 (Div. 2), which will be held on 12.02.2021 17:50 (Московское время). This round will be rated for participants with rating lower than 2100.

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

We would like to thank

• MrBrionix, MyK_00L, taulant and TheScrasse (a.k.a. the jungkook official fanclub) for inventing and preparing the problems.
• isaf27 for the great coordination and the valuable help he provided at any time.
• antontrygubO_o for not being involved and hence not rejecting any problem.
• MikeMirzayanov for creating Codeforces and Polygon.

Last but not least, we also want to thank the testers: armyalpaca, dario2994, davi_bart, DeadlyCritic, franfill, HIS_GRACE, kclee2172, lorenzoferrari, manik.jain, mattysal, namanbansal013, Osama_Alkhodairy, Prakash11, rocks03, Shusaku, simpatine, stefdasca and Retired_cherry.

The score distribution will be announced soon.

We hope you'll like the problemset!

UPD1: The score distribution is $$$500 - 1000 - 1500 - 1750 - 2500 - 3000$$$.

UPD2: For technical reasons, the round was postponed by 15 minutes. Sorry for that, good luck on round!

UPD3: Editorial is out.

UPD4: Congratulations to the winners!

Div. 1 + Div. 2:

1. Muffinhead
2. jiangly
3. neal
4. rustylake
5. SSRS_

Div. 2:

1. rustylake
2. Join_VNOI_Discord
3. Mr_Eight
4. _Froggy_
5. Brookli

First to solve each problem:

A: m_99
B: kmjp
C: Brookli
D: enoone
E: w0nsh
F: rainboy

Hey Codeforces,

Don’t miss tomorrow’s SIT STAR Contest 2021, organized by the Schaffhausen Institute of Technology (SIT) in Switzerland to promote interest in Computer Science and Software Engineering.

The online coding contest will be happening tomorrow on February 10, from 8:00 to 12:00 am UTC.

During the event, you will face 12 or 13 algorithmic programming challenges of increasing difficulty (Div 4, Div 3, Div 2). The contest is open to all, and you can sign up for free here.

Why participate?

Apart from being a fun coding experience, SIT STAR Contest 2021 is the easiest way to enroll in a fully-funded master’s program in Computer Science and Software Engineering at SIT. The prizes at stake range from small souvenirs from Switzerland to tuition waivers for master’s students to full scholarships the cover both tuition and living expenses.

Note that you must hold a bachelor’s degree or be in the final year of your studies to join SIT in September 2021.

Don’t miss your chance to continue your studies at SIT!

More about SIT

Schaffhausen Institute of Technology is founded by entrepreneurs, led by scientists, and advanced by world-class researchers. Based in Schaffhausen, Switzerland, SIT drives knowledge through science across many projects. In particular, SIT Master’s offers a blended degree in Computer Science and Software Engineering that you can attend in person, online, or as a mix of both.

Dear friends,

I am honoured to present you "Adolescent Grigore Moisil" (AGM) International Programming Contest (7th 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 20th February. The problems are set up fully by university students, medalists in national and international competitions (IOI, BOI, CEOI, etc.).

We are looking forward to international participants, especially those who want to participate in the final round (which is set to be in Bucharest, Romania, this summer, but there are chances to be held also online due to the pandemic situation; we will come with further details). You can register here until 19th February at 17:00 GMT.

Finally, I am more than delighted to present you our team: patrick.sava (the heart of the project), geniucos, average_frog_enjoyer, munteanuvlad98, Stelutzu, Alex18mai, teoionescu, bogdan10bos, carabet.cosmin, Stefan_Radu, Mihai22e, Mihneac, vreaudelftpls, eman98, GinguIonut, caesar2001, 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

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

Thank you very much,

George

Hello, Codeforces!

I'm very glad to invite you to my contest Codeforces Round 700 (Div. 1) and Codeforces Round 700 (Div. 2), which will be held on Feb/07/2021 17:35 (Moscow time). In both divisions, you will be given 6 problems and 2 hours 15 minutes to solve them. One of these problems is interactive, please see the guide of interactive problems if you are not familiar with it.

I would like to thank:

• antontrygubO_o for rejecting problems his amazing coordination and discussion.

• zjq2863974342 for all his rejected problems becoming the protagonist "Homer" in our problems in honor of his contribution.

• lavender730 for all her rejected problems sharing problem ideas and selecting the date of this round.

• choutii for discussion and being the first tester of this round (even before the testing phase).

• 300iq, Retired_cherry, Aditya_Mittal_31, dorijanlendvaj, gamegame, coderz189, Sugar_fan, HIS_GRACE, Invincible06, jiangshibiao, JOHNKRAM, littlefriend, lucifer1004, lyuankai, Milesian, mohammedehab2002, moreD, p_b_p_b and kalki411 for testing and their invaluable feedback.

• MikeMirzayanov for the great Codeforces and Polygon!

I have tried my best to write clear problem statements and make strong pretests. I hope you like the problems and enjoy the round.

The anti-traditional score distribution (yes, very early, that's why we call it anti-traditional; I love early score distributions!) is given as follows:

• Div. 1: $$$500 - (750 + 750) - 1500 - 2250 - 4000$$$

• Div. 2: $$$500 - 1000 - 1500 - (1500 + 1500) - 3000$$$

UPD: Editorial is out.

UPD1: We are sorry for the issue with the problem D2B and for D2C=D1A turning out to be well-known. Constraints for D2B were changed from $$$10^9$$$ to $$$10^6$$$ and all submissions which didn't get AC during the contest were rejudged.

We apologize once again and thank you for your participation.

UPD2 Congratulations to the winners:

Div 1:

1. Petr

2. A.K.E.E.

3. ko_osaga

4. Isonan

5. Benq

Also congratulations to hos.lyric (the only contestant who solved E during contest time!)

Div 2:

1. 5002ryx

2. AlanChen

3. whx1003

4. zkou

5. Ritos__