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By awoo, history, 6 years ago, translation, In English

1082A - Vasya and Book

Tutorial
Solution (Ajosteen)

1082B - Vova and Trophies

Tutorial
Solution (Ajosteen)

1082C - Multi-Subject Competition

Tutorial
Solution (adedalic)

1082D - Maximum Diameter Graph

Tutorial
Solution (PikMike)

1082E - Increasing Frequency

Tutorial
Solution (adedalic)

1082F - Speed Dial

Tutorial
Solution (PikMike)

1082G - Petya and Graph

Tutorial
Solution (Ajosteen)

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By awoo, history, 6 years ago, translation, In English

On Nov/28/2018 17:35 (Moscow time) Educational Codeforces Round 55 (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 extented ACM 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 7 problems and 2 hours to solve them.

The problems were invented and prepared by Mike MikeMirzayanov Mirzayanov, Roman Roms Glazov, Adilbek adedalic Dalabaev, Vladimir vovuh Petrov, Ivan BledDest Androsov and me.

Good luck to all participants!

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

Hello Codeforces!

We are excited to announce that the Hello Muscat Programming Bootcamp registration is open! The camp will take place from March 9th to March 15th, 2019, and our early bird discount of 15% is going until December 15th!

This next edition in our Hello Programming Bootcamp will run in parallel with the traditional Moscow ICPC Workshop — both Bootcamps’ contests will be identical, and contestants will be able to see their position in the General Leaderboard. Every day, both camps will be competing simultaneously, 4,000 kilometers from each other!

REGISTER FOR THE BOOTCAMP

We would also like to remind you that the deadline for applying to the Master’s in Robotics programme scholarship will close November 30th, so we encourage you to check out the website to see the all the requirements and apply!

APPLY HERE

UPD: You can discuss the problems after the contest at a local Discord server.

UPD2:

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 I_love_Tanya_Romanova 7 157
2 theodor.moroianu 7 330
3 halyavin 7 361
4 Radewoosh 6 158
5 palayutm2001 6 190

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 131:-8
2 zdw1999 55:-4
3 MarcosK 42:-1
4 ismagilov.code 64:-48
5 garipov.roma 48:-24

1354 successful hacks and 1065 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A I_love_Tanya_Romanova 0:02
B Dalgerok 0:04
C I_love_Tanya_Romanova 0:08
D hitman623 0:15
E lqs2015 0:11
F ko_osaga 0:47
G RomaWhite 0:08

UPD3: Editorial is out

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By awoo, history, 6 years ago, translation, In English

1076A - Minimizing the String

Tutorial
Solution (Vovuh)

1076B - Divisor Subtraction

Tutorial
Solution (PikMike)

1076C - Meme Problem

Tutorial
Solution (adedalic)

1076D - Edge Deletion

Tutorial
Solution (BledDest)

1076E - Vasya and a Tree

Tutorial
Solution (Ajosteen)

1076F - Summer Practice Report

Tutorial
Solution (PikMike)

1076G - Array Game

Tutorial
Solution (BledDest)

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By awoo, history, 6 years ago, translation, In English

On Nov/12/2018 17:35 (Moscow time) Educational Codeforces Round 54 (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 extented ACM 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 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 and me.

Good luck to all participants!

UPD: There certainly will be a discussion of the problems on the local Discord server shortly after the contest ends. I might join it as well)

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Anadi 7 266
2 HIR180 6 129
3 mrscherry 6 152
4 Vergara 6 158
5 Jeel_Vaishnav 6 185

Congratulations to the best hackers:

Rank Competitor Hack Count
1 teapotd 100:-4
2 vlad.raw 52:-5
3 MarcosK 32
4 tataky 28:-5
5 knotValid 23
721 successful hacks and 668 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A Dalgerok 0:01
B Nazikk 0:03
C neal 0:03
D tamref 0:14
E shadowatyy 0:13
F killer_god 0:34
G lxrvelory 1:03

UPD2: There was an error in problem D which caused some incorrect solutions to get accepted. We will investigate the number of users who were affected by this issue and decide whether the round is rated.

UPD3: We discussed the issue and came up with the following decision:

Those who got accepted earlier and get WA now won't be affected by rating changes. For everyone else (for those who got correct verdict) the contest will be rated.

UPD4: Editorial is out

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By awoo, history, 6 years ago, translation, In English

1073A - Diverse Substring

Tutorial
Solution (PikMike)

1073B - Vasya and Books

Tutorial
Solution (Ajosteen)

1073C - Vasya and Robot

Tutorial
Solution (Ajosteen)

1073D - Berland Fair

Tutorial
Solution (PikMike)

1073E - Segment Sum

Tutorial
Solution (Vovuh)

1073F - Choosing Two Paths

Tutorial
Solution (Vovuh)

1073G - Yet Another LCP Problem

Tutorial
Solution (adedalic)

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By awoo, history, 6 years ago, translation, In English

On Oct/25/2018 17:35 (Moscow time) Educational Codeforces Round 53 (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 extented ACM 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 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 and me.

Good luck to all participants!

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

Hey Codeforces! We want to remind you that the Scholarship for the Master’s in Robotics programme, which starts on January 7th 2019, has an application deadline of November 12th, 2018.

Harbour.Space University and Remy Robotics are collaborating to offer graduate students from anywhere in the world a once in a lifetime opportunity, a fully funded scholarship for Harbour.Space University’s Master’s Programme in Robotics.

The scholarship value is €34.900 and it includes:

  • Complete coverage of the University tuition fee (€22,900)

  • Internship at Remy Robotics (20h per week during 1 year)

  • €1,000 per month during 1 year (Internship earnings)

Apply here

UPD: vovuh and me will be waiting for you on the community Discord server shortly after the contest to discuss the problems.

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 pekempey 7 305
2 ko_osaga 7 578
3 Lewin 6 216
4 fanache99 6 226
5 natsugiri 6 257

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 238:-15
2 Laggy 64:-14
3 MarcosK 59:-9
4 Mistra 8:-1
5 LordVoldebug 7:-1
482 successful hacks and 684 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A Dalgerok 0:01
B dorijanlendvaj 0:02
C fanache99 0:10
D bazsi700 0:13
E DAyamaCTF 0:21
F Noam527 0:48
G ko_osaga 0:24

UPD2: Editorial is published

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By awoo, history, 6 years ago, In English

1065A - Vasya and Chocolate

Tutorial
Solution (Ajosteen)

1065B - Vasya and Isolated Vertices

Tutorial
Solution (Ajosteen)

1065C - Make It Equal

Tutorial
Solution (Ajosteen)

1065D - Three Pieces

Tutorial
Solution (PikMike)

1065E - Side Transmutations

Tutorial
Solution (PikMike)

1065F - Up and Down the Tree

Tutorial
Solution (adedalic)

1065G - Fibonacci Suffix

Tutorial
Solution (BledDest)

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By awoo, 6 years ago, translation, In English
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By awoo, history, 6 years ago, translation, In English

On Sep/20/2018 17:45 (Moscow time) Educational Codeforces Round 51 (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 extented ACM 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 7 problems and 2 hours to solve them.

The problems were invented and prepared by Roman Roms Glazov, Ivan BledDest Androsov and me.

Good luck to all participants!

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

Harbour.Space University is proud to announce new partnerships for this year’s Hello Barcelona Programming Bootcamp — VTB and Indeed Tokyo, with the addition of team sponsors Phaze Ventures and Spark Labs.

VTB, the largest international bank based in Eastern Europe, continues to be an official partner of our Hello Programming Bootcamp series, adding further quality to the 3rd edition of the Hello Barcelona Programming Bootcamp by bringing their own participants, as well as by supporting top teams from around the world.

Indeed Tokyo is Japan’s branch of the #1 employment website in the world, giving job seekers free access to millions of jobs from thousands of company websites and job boards. As they sponsor for the second year in a row, Indeed continues to offer the best job opportunities to the boot camp participants as they gather in Barcelona from September 26 to October 4, 2018.

UPD: There was a bug in testset and validator for problem F, we are currently fixing the issue. The statement included the correct resrictions. We will rejudge all the solutions as soon as possible. The round can become unrated, we are discussing this at the moment.

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 kmjp 6 210
2 MrDindows 6 223
3 elykuil 6 242
4 Nisiyama_Suzune 6 274
5 Fekete 6 274

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 299:-14
2 Laggy 100:-10
3 greencis 29:-2
4 Volkov_Ivan 19
5 dorijanlendvaj 13
694 successful hacks and 497 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A traxex 0:03
B answhldkd 0:02
C ainta 0:06
D greencis 0:07
E tfg 0:38
F baggins 0:26
G yasugongshang 0:56

UPD2: We investigated the issue to get the following results. 10 people were noticeably affected (that took them more than 3 minutes of the working time). Round will surely be rated for other participants. As for the affected participants, we will look into the rating changes and revert them in case they are negative (set the participant into the unofficial participation mode).

UPD3: Editorial is out

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By awoo, history, 6 years ago, translation, In English

1036A - Function Height

Tutorial
Solution (Vovuh)

1036B - Diagonal Walking v.2

Tutorial
Solution (Vovuh)

1036C - Classy Numbers

Tutorial
Solution with combinatorics (PikMike)
Solution with precalc (PikMike)

1036D - Vasya and Arrays

Tutorial
Solution (Ajosteen)

1036E - Covered Points

Tutorial
Solution (PikMike)

1036F - Relatively Prime Powers

Tutorial
Solution (PikMike)

1036G - Sources and Sinks

Tutorial
Solution (BledDest)

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By awoo, history, 6 years ago, translation, In English

On Sep/07/2018 17:35 (Moscow time) Educational Codeforces Round 50 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 extented ACM 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 7 problems and 2 hours to solve them.

The problems were invented and prepared by Vladimir vovuh Petrov, Roman Roms Glazov, Ivan BledDest Androsov, Maxim Neon Mescheryakov and me.

Good luck to all participants!

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

Hi Codeforces!

We are excited to announce our Work & Study Programme, geared towards diving into the worlds of Computer Science, Data Science, and Robotics, while kick starting a fulfilling paid internship with one of our industrial partners!

Required Education:

Degree in Robotics or Computer, Electrical, Mechanical Engineering or related disciplines

Qualifications and skills:

  • Hands-on robotic programming
  • Ideally experience within the automotive manufacturing sector
  • Knowledge understanding of robot control interface with ancillary equipment
  • Use of robot simulation packages
  • Deep experience with all things robotic, from infrastructure-free autonomy, to ROS, computer vision, and machine learning
  • Experience working with robot parts and components, developing robotics devices
  • Ability to concurrently manage multiple diverse and often complex issues and / or projects at the nexus of software, sensors, and hardware

If you are interested in this opportunity, APPLY HERE!

Should you be selected, we will invite you to a series of interviews with admissions, and our industrial partners.

Our programmes are both fundamental and practical. Upon joining, you start working with professionals from admired technology, design and communications companies. You will have strong technical and academic support, alongside industrial experience. This is a unique opportunity to benefit from both worlds of education and industry, in one of the most innovative cities Western Europe has to offer.

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 eddy1021 7 298
2 bmerry 7 301
3 LYJabc 7 547
4 thjchph4trjnh 7 551
5 BigBag 6 192

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 240:-18
2 greencis 47:-3
3 vinuthegr8 15
4 antguz 14
5 cubercsl 14:-9
497 successful hacks and 440 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A xiaowuc1 0:01
B TOSHINO_KYOKO 0:06
C cb_Adam 0:07
D BoolX 0:08
E bmerry 0:24
F rkm0959 0:10
G apink 0:28

UPD: Editorial is uploaded

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By awoo, history, 6 years ago, In English

1027A - Palindromic Twist

Tutorial
Solution (PikMike)

1027B - Numbers on the Chessboard

Tutorial
Solution (Vovuh)

1027C - Minimum Value Rectangle

Tutorial
Solution (PikMike)

1027D - Mouse Hunt

Tutorial
Solution (adedalic)

1027E - Inverse Coloring

Tutorial
Solution (PikMike) O(n^3)
Solution (BledDest) O(n^2)

1027F - Session in BSU

Tutorial
Solution (Vovuh)
Solution (Vovuh) Kuhn's Algorithm

1027G - X-mouse in the Campus

Tutorial
Solution (adedalic)

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By awoo, history, 6 years ago, translation, In English

On Aug/18/2018 17:35 (Moscow time) Educational Codeforces Round 49 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 extented ACM 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 7 problems and 2 hours to solve them.

The problems were invented and prepared by Vladimir vovuh Petrov, Adilbek adedalic Dalabaev, Ivan BledDest Androsov, Mike MikeMirzayanov Mirzyanov and me.

Good luck to all participants!

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

Hi Codeforces!

Our Hello Barcelona Programming Bootcamp will be kicking off next month from Sept 26 — Oct 4, and we’d love to see you there!

The boot camp will once again feature the all-time greats Mike MikeMirzayanov Mirzayanov, Andrey andrewzta Stankevich, Michael Endagorion Tikhomirov, Gleb GlebsHP Evstropov, Artem VArtem Vasilyev, Ivan ifsmirnov Smirnov and other world renowned Russian coaches to train the participants.

You will be competing and learning side by side with some of the greatest teams in the world, while learning from the best coaches the ICPC has to offer.

Be sure to register before September 1st so everyone has time to get visas if needed, and of course for the Early Bird Discount of 5% or the Loyalty Discount* of 20% off registration for the boot camp!

*The loyalty discount is offered to universities and individual participants that took part in Hello Barcelona Bootcamps and Moscow Workshops ICPC.

Learn more about Barcelona ICPC Bootcamp

You can ask any questions by email: [email protected]

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Um_nik 7 179
2 isaf27 7 343
3 BlackPuppy 7 357
4 eddy1021 6 157
5 ppc_qjd 6 176

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 200:-25
2 eR6 87:-58
3 Winniechen 35:-13
4 jhonber 29:-1
5 Kaban-5 19
697 successful hacks and 674 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A arknave 0:02
B eddy1021 0:06
C bekzhan97 0:12
D teja349 0:12
E step_by_step 0:10
F lee_sin 0:24
G uwi 0:39

UPD: The editorial is posted

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By awoo, history, 6 years ago, translation, In English

On Aug/03/2018 17:45 (Moscow time) Educational Codeforces Round 48 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 extented ACM ICPC rules. 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 7 problems and 2 hours to solve them.

The problems were invented and prepared by Ivan BledDest Androsov, Roman Roms Glazov, Adilbek adedalic Dalabaev, Vladimir vovuh Petrov and me.

Good luck to all participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 eddy1021 7 299
2 ppc_qjd 6 240
3 halyavin 6 248
4 BigBag 6 250
5 IcePrince_1968 6 286

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 80:-21
2 Doriath 45:-10
3 antguz 25:-1
4 applese 12
5 Neon 11:-2
236 successful hacks and 417 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A bazsi700 0:01
B bazsi700 0:05
C yjq_naiiive 0:17
D teja349 0:10
E yjq_naiiive 0:49
F eddy1021 0:41
G comfi 1:16

UPD: Editorial

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By awoo, history, 6 years ago, translation, In English

1009A - Game Shopping

Tutorial
Solution (Vovuh)

1009B - Minimum Ternary String

Tutorial
Solution (Vovuh)

1009C - Annoying Present

Tutorial
Solution (PikMike)

1009D - Relatively Prime Graph

Tutorial
Solution (PikMike)

1009E - Intercity Travelling

Tutorial
Solution (BledDest)

1009F - Dominant Indices

Tutorial
Solution (BledDest)

1009G - Allowed Letters

Tutorial
Solution (Bleddest)

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By awoo, history, 6 years ago, translation, In English

Hello Codeforces!

On Jul/14/2018 17:35 (Moscow time) Educational Codeforces Round 47 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 extented ACM ICPC rules. 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 7 problems and 2 hours to solve them.

The problems were invented and prepared by Ivan BledDest Androsov, Vladimir vovuh Petrov, Maksim Neon Mescheryakov, Aslan Timurovich Tamaev and me.

Good luck to all participants!

I also have a message from our partner, Harbour.Space University:

Hi Codeforces!

We want to remind everyone that the Hello Barcelona Programming Bootcamp is right around the corner, and we’d love to see you there!

Our boot camp will once again feature the all-time greats Mike MikeMirzayanov Mirzayanov, Andrey andrewzta Stankevich, Michael Endagorion Tikhomirov, Gleb GlebsHP Evstropov, Artem VArtem Vasilyev, Ivan ifsmirnov Smirnov and other world renowned Russian coaches to train the participants.

We would also like to extend a welcome to some of the newest teams to join us from Colorado School of Mines, University of British Columbia and Reykjavík University.

Be sure to register before August 1st so everyone has time to get visas if needed, and of course for the Early Bird Discount of 15% or the Loyalty Discount* of 20% off registration for the boot camp!

*The loyalty discount is offered to universities and individual participants that took part in Hello Barcelona Bootcamps and Moscow Workshops ICPC.

Learn more about Barcelona ICPC Bootcamp

You can ask any questions by email: [email protected]

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 tribute_to_Ukraine_2022 7 159
2 hohomu 7 274
3 guille 7 338
4 radoslav11 7 580
5 waynetuinfor 6 148

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 689:-132
2 2014CAIS01 91:-13
3 Al-Merreikh 20:-1
4 Ali_Pi 16:-3
5 gsparken 15:-3
978 successful hacks and 798 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A Harpae 0:01
B eddy1021 0:05
C tribute_to_Ukraine_2022 0:09
D BARPITF 0:09
E Roundgod 0:19
F radoslav11 0:15
G chemthan 0:28

UPD: The editorial is posted

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By awoo, history, 6 years ago, translation, In English

990A - Commentary Boxes

Tutorial
Solution (PikMike)

990B - Micro-World

Tutorial
Solution (adedalic)

990C - Bracket Sequences Concatenation Problem

Tutorial
Solution (Ajosteen)

990D - Graph And Its Complement

Tutorial
Solution (Ajosteen)

990E - Post Lamps

Tutorial
Solution (PikMike)

990F - Flow Control

Tutorial
Solution (PikMike)

990G - GCD Counting

Tutorial
Solution with Möbius (Bleddest)
Solution with centroid (adedalic)

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By awoo, history, 6 years ago, In English

Hello Codeforces!

On Jun/10/2018 13:05 (Moscow time) Educational Codeforces Round 45 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 extented ACM ICPC rules. 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 7 problems and 2 hours to solve them.

The problems were invented and prepared by Adilbek adedalic Dalabaev, Roman Roms Glazov, Ivan BledDest Androsov, Mike MikeMirzayanov Mirzayanov and me.

Good luck to all participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 KrK 7 225
2 isaf27 7 231
3 BigBag 7 325
4 Motarack 7 327
5 TangentDay 7 331

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 202:-52
2 2014CAIS01 26:-2
3 djm03178 20
4 bitcoin 19
5 antguz 25:-17
549 successful hacks and 525 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A tzuyu_chou 0:01
B DoomzGay 0:05
C 562225807 0:08
D teja349 0:12
E eddy1021 0:18
F nhho 0:45
G AChen142857 0:14

UPD: Editorial is out

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By awoo, history, 6 years ago, translation, In English

985A - Chess Placing

Tutorial
Solution (Vovuh)

985B - Switches and Lamps

Tutorial
Solution (Vovuh)

985C - Liebig's Barrels

Tutorial
Solution (adedalic)

985D - Sand Fortress

Tutorial
Solution (PikMike)

985E - Pencils and Boxes

Tutorial
Solution (PikMike)

985F - Isomorphic Strings

Tutorial
Solution (adedalic)

985G - Team Players

Tutorial
Solution (adedalic)

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By awoo, history, 6 years ago, translation, In English

Hello Codeforces!

On May/21/2018 17:45 (Moscow time) Educational Codeforces Round 44 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 extented ACM ICPC rules. After the end of the contest you will have one day to hack any solution you want. You will have access to copy any solution and test it locally.

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

The problems were prepared by Adilbek adedalic Dalabaev, Vladimir vovuh Petrov and me.

Good luck to all participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Benq 6 143
2 crhkr 6 202
3 mjhun 6 210
4 nhho 6 210
5 krijgertje 6 223

Congratulations to the best hackers:

Rank Competitor Hack Count
1 step_by_step 248:-25
2 greencis 31:-6
3 zero-light-some 15
4 Necrozma 12
5 Codefocres 11:-1
703 successful hacks and 490 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A dotorya 0:01
B dotorya 0:03
C dotorya 0:10
D Benq 0:21
E ThePilgrim 0:07
F Deemo 0:49
G Marco_L_T 0:44

UPD: Editorial is uploaded

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By awoo, history, 7 years ago, translation, In English
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By awoo, history, 7 years ago, translation, In English
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By awoo, history, 7 years ago, translation, In English

Hello Codeforces!

On February 16, 18:05 MSK Educational Codeforces Round 38 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 Div. 2. It will be held on extented ACM ICPC rules. 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 7 problems and 2 hours to solve them.

The problems were prepared by Ivan BledDest Androsov, Sahand Xahandd Alitanloo and me.

Thanks Mike MikeMirzayanov Mirzayanov for great system Polygon!

Good luck to all participants!

UPD: Since there will be another Div. 2 contest soon, the hacking phase will be shorter (only 12 hours). Before CF Round 464 we will actualize the registrations in such a way that Div. 2 will be officially registered, and Div. 1 participants — unofficially.

UPD2: We also have a message from our partners Harbour.Space:

We are excited to announce that some of the world’s strongest teams will come to our Hello India x Russia Programming Bootcamp: MIPT and all top India’s Universities that qualified to the World Finals!

As always, the boot camp isn’t only about the training — we’re in the process of getting renowned keynote speakers from all over the globe to come and speak about life and all the opportunities at your fingertips after ACM-ICPC.

We look forward to seeing you all there this spring! For those of you who haven't registered, there's still time.

Register here

If you have any questions we can help you with, please connect with us:

Phone number: +34 674 291 422 Email Address: [email protected]

UPD3: Editorial is published

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By awoo, history, 7 years ago, translation, In English

Hello Codeforces!

On December 28, 17:05 MSK Educational Codeforces Round 35 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 Div. 2. It will be held on extented ACM ICPC rules. After the end of the contest you will have one day to hack any solution you want. You will have access to copy any solution and test it locally.

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

The problems were prepared by Ivan BledDest Androsov, Vladimir vovuh Petrov, Alexey Perforator Ripinen and me.

Thanks Mike MikeMirzayanov Mirzayanov for great system Polygon!

Good luck to all participants!

We also have a message from our partners, Harbour.Space University:

Hello everyone!

Registration is open for our upcoming 1st Hello India x Russia Programming Bootcamp, with 20 teams signed up and counting, and we are looking forward to seeing you and your teammates in India this March!

More information

Register here

UPD: There will be 7 problems!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 bmerry 7 212
2 uwi 7 216
3 halyavin 7 287
4 hesihesiwujiuwu 7 314
5 voidmax 7 337

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 328:-26
2 Kilani 107:-6
3 Aemon 91:-33
4 algmyr 57:-4
5 Yazdanra 29:-9

1761 successful hacks and 1237 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A IHaveInt 0:01
B Benq 0:03
C WZYYN 0:06
D PrashantM 0:08
E perchema 0:15
F pekempey 0:38
G chemthan 0:21

UPD2: Editorial is out

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By awoo, history, 7 years ago, translation, In English
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