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By pikmike, history, 10 days ago, translation, In English,

1373A - Donut Shops

Idea: Roms

Tutorial
Solution (pikmike)

1373B - 01 Game

Idea: Roms

Tutorial
Solution (Roms)

1373C - Pluses and Minuses

Idea: Roms

Tutorial
Solution (Roms)

1373D - Maximum Sum on Even Positions

Idea: vovuh

Tutorial
Solution (vovuh)

1373E - Sum of Digits

Idea: BledDest

Tutorial
Solution 1 (BledDest)
Solution 2 (pikmike)

1373F - Network Coverage

Idea: adedalic

Tutorial
Solution 1 (adedalic)
Solution 2 (Ne0n25)

1373G - Pawns

Idea: Roms and BledDest

Tutorial
Solution (Roms)

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By pikmike, history, 12 days ago, translation, In English,

Hello Codeforces!

On Jun/25/2020 17:35 (Moscow time) Educational Codeforces Round 90 (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 Ne0n25 Mescheryakov and me. Also huge thanks to Mike MikeMirzayanov Mirzayanov for great systems Polygon and Codeforces.

Good luck to all the participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Geothermal 7 130
2 ksun48 7 143
3 300iq 7 147
4 vepifanov 7 168
5 Radewoosh 7 175

Congratulations to the best hackers:

Rank Competitor Hack Count
1 EduPeres 40
2 Grey_Matter 39:-3
3 lx430621 26:-1
4 killa_vanilla 25:-5
5 checkingagain 17:-1
351 successful hacks and 375 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A Geothermal 0:01
B ksun48 0:01
C ksun48 0:03
D Noureldin 0:09
E Geothermal 0:22
F ElOrdyh 0:15
G dario2994 0:29

UPD: Editorial is out

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By pikmike, history, 3 weeks ago, translation, In English,

1366A - Shovels and Swords

Idea: Roms

Tutorial
Solution (Roms)

1366B - Shuffle

Idea: Roms

Tutorial
Solution (Roms)

1366C - Palindromic Paths

Idea: BledDest

Tutorial
Solution (BledDest)

1366D - Two Divisors

Idea: adedalic

Tutorial
Solution (adedalic)

1366E - Two Arrays

Idea: Roms

Tutorial
Solution (Roms)

1366F - Jog Around The Graph

Idea: Ne0n25

Tutorial
Solution (pikmike)

1366G - Construct the String

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

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

Hello Codeforces!

On Jun/11/2020 17:35 (Moscow time) Educational Codeforces Round 89 (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 Ne0n25 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:

Codeforces and Harbour.Space

Hey Codeforces!

A couple of weeks ago, we had the pleasure of hosting a webinar featuring Sergey Gordeichik, CIO of the Inception Institute of Artificial Intelligence and Director of the University’s Cybersecurity Programme.

In his talk, Sergey shared his expertise and insights on how AI is being used both positively and negatively during the COVID-19 global pandemic. He touched on topics such as the ethics of using this technology, and how it was implemented during each phase of the pandemic.

We know not everyone had the chance to tune in during the webinar, so we thought you’d be interested in having a look at the slide deck of his presentation.

You can check it out here.

If this was interesting for you, let us know in the comments, and we’ll do our best to try and provide more content like this. Keep an eye out for the final two talks in our webinar series — they might be of interest to you :)

Finally, don’t forget that this July, Sergey is teaching a course on the Cybersecurity of Cloud, Big Data, and AI. The course will be 100% online, so be sure to check it out on our website if you’re interested. Here’s the link.

That’s all from us!

Good luck in the round, and we’ll see you soon!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 ksun48 7 188
2 saketh 7 264
3 hank55663 7 320
4 kefaa2 6 109
5 Radewoosh 6 126

Congratulations to the best hackers:

Rank Competitor Hack Count
1 Hakiobo 70
2 napgod_pk 67:-12
3 Zaher 71:-21
4 VladProg 60
5 BohdanPastuschak 62:-26

1115 successful hacks and 2003 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A neal 0:00
B neal 0:02
C ksun48 0:05
D BohdanPastuschak 0:05
E ksun48 0:15
F kort0n 0:51
G rainboy 0:25

UPD: Editorial is out

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By pikmike, history, 5 weeks ago, translation, In English,

1359A - Berland Poker

Idea: BledDest

Tutorial
Solution 1 (BledDest)
Solution 2 (BledDest)

1359B - New Theatre Square

Idea: BledDest

Tutorial
Solution (pikmike)

1359C - Mixing Water

Idea: adedalic

Tutorial
Solution (pikmike)

1359D - Yet Another Yet Another Task

Idea: BledDest

Tutorial
Solution (pikmike)

1359E - Modular Stability

Idea: BledDest

Tutorial
Solution (BledDest)

1359F - RC Kaboom Show

Idea: BledDest

Tutorial
Solution (pikmike)

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By pikmike, history, 6 weeks ago, translation, In English,

Hello Codeforces!

On May/28/2020 17:35 (Moscow time) Educational Codeforces Round 88 (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 Ne0n25 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:

Codeforces and Harbour.Space

Hey Codeforces!

As you may remember, we have a free webinar series starring our all-star faculty members who share valuable content and insiders’ knowledge that you don’t get to learn about in traditional classrooms.

Join us tomorrow, Thursday, May 28 at 12h (BCN) / 17h (BKK) to watch Sergey Gordeychik, CIO of the Inception Institute of Artificial Intelligence, share his expertise and insights in his “Digital Lockdown: AI against COVID-19” session. Sergey will discuss how AI is being used both positively and negatively during the COVID-19 global pandemic. Tune in for some practical examples of how companies are using AI to innovate and disrupt during a time of crisis, exploring topics like Medical Imaging for CT analysis, diagnosis and mass surveillance.

By participating in this webinar you will get a certificate of participation, a special digital gift from Sergey, and stand a chance to win a FREE 3-week module at Harbour.Space University depending on the availability and prerequisites of the course.

See you tomorrow, and good luck on your round!

Reserve your spot now!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 kefaa2 6 174
2 bmerry 6 219
3 dlalswp25 6 233
4 hepth 6 238
5 Volkov_Ivan 6 251

Congratulations to the best hackers:

Rank Competitor Hack Count
1 Hideki_Ryuga_L 37
2 KonaeAkira 19:-1
3 ujjwalsingh30 18:-1
4 veteran_ 14
5 hashlib 13
318 successful hacks and 469 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A andryusha_na_knopke 0:01
B thech0sen1 0:03
C IAKWF 0:11
D Kerim.K 0:06
E HeHere 0:06
F user202729_ 0:44

UPD: Editorial is out

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By pikmike, history, 7 weeks ago, translation, In English,

1354A - Alarm Clock

Idea: BledDest

Tutorial
Solution (pikmike)

1354B - Ternary String

Idea: BledDest

Tutorial
Solution (BledDest)

1354C1 - Simple Polygon Embedding

Idea: adedalic

Tutorial

1354C2 - Not So Simple Polygon Embedding

Idea: adedalic

Tutorial
Solution (adedalic)

1354D - Multiset

Idea: BledDest

Tutorial
Solution (BledDest)

1354E - Graph Coloring

Idea: BledDest

Tutorial
Solution (pikmike)

1354F - Summoning Minions

Idea: BledDest

Tutorial
Solution 1 (BledDest)
Solution 2 (neal)
Solution 3 (pikmike)

1354G - Find a Gift

Idea: adedalic

Tutorial
Solution (adedalic)

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By pikmike, history, 7 weeks ago, translation, In English,

Hello Codeforces!

On May/17/2020 12:20 (Moscow time) Educational Codeforces Round 87 (Rated for Div. 2) will start.

Please notice the unusual time.

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 Ne0n25 Mescheryakov and me. Also huge thanks to Mike MikeMirzayanov Mirzayanov for great systems Polygon and Codeforces.

Also thanks to Neal neal Wu for testing.

Good luck to all the participants!

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

Codeforces and Harbour.Space

Hi Codeforces!

We would like to invite you to a very special webinar called Digital Lockdown: AI against COVID-19, by Sergey Gordeychik, director of our Cyber Security programme.

Sergey is CIO of Inception Institute of Artificial Intelligence, and former CTO at Kaspersky.

During this webinar, Sergey will share his expertise and insights on how AI is being used both positively and negatively, during the COVID-19 global pandemic. Tune in for some practical examples of how companies are using AI to innovate and disrupt during a time of crisis, exploring topics like Medical Imaging for CT analysis, diagnosis and mass surveillance.

Join us on Thursday, May 28th at 12h (BCN) to gain knowledge and deepen your understanding about how we can use AI to solve both operational and societal problems.

By participating in this 1hour webinar you will get a certificate of participation, a special digital gift from Sergey, and have the chance to win a FREE 3-week module at Harbour.Space University, depending on the availability and prerequisites of the course.

Reserve your spot now!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 square1001 8 294
2 Anadi 8 305
3 tfg 8 681
4 kefaa2 7 192
5 xay542I 7 248

Congratulations to the best hackers:

Rank Competitor Hack Count
1 qwscaln 29:-2
2 im_Ankit 5
3 lvao-x 3:-1
4 the_redback 3:-1
5 WICK_ED 2:-1
142 successful hacks and 828 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A fedoseev.timofey 0:02
B Ashishgup 0:03
C1 hitman623 0:04
C2 square1001 0:15
D Not-Afraid 0:10
E autumn_eel 0:17
F squarepants 0:47
G riantkb 0:37

UPD: Editorial is out

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By pikmike, history, 2 months ago, translation, In English,

1342A - Road To Zero

Idea: BledDest and adedalic

Tutorial
Solution (Roms)

1342B - Binary Period

Idea: adedalic

Tutorial
Solution (adedalic)

1342C - Yet Another Counting Problem

Idea: BledDest and adedalic

Tutorial
Solution (BledDest)

1342D - Multiple Testcases

Idea: BledDest

Tutorial
Solution (pikmike)

1342E - Placing Rooks

Idea: BledDest

Tutorial
Solution (BledDest)

1342F - Make It Ascending

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

Read more »

Tutorial of div2 B-C #1
 
 
 
 
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By pikmike, history, 2 months ago, translation, In English,

Hello Codeforces!

On Apr/26/2020 17:35 (Moscow time) Educational Codeforces Round 86 (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 Ne0n25 Mescheryakov and me. Also huge thanks to Mike MikeMirzayanov Mirzayanov for great systems Polygon and Codeforces.

Special thanks to Mikhail darnley Dvorkin for helping in round preparation!

Good luck to all the participants!

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

Codeforces and Harbour.Space

Hi Codeforces!

You really went for it in the last Educational Round! We had an all-time high participation of 21750 people :) We are happy to support such an awesome community, and look forward to growing these numbers in the future!

We are searching for diamonds in the rough — driven, talented humans, passionate about technology and design, undefined by nationality, gender and cultural background. We know that no diamond is born polished, so our mission is to identify and support as many talented young individuals as we can, so that they can fulfill their potential and secure the future they deserve.

If you are graduating or have already completed a bachelor's degree, we are waiting for your applications for fully-funded Master's degree scholarships by the link below.

APPLY NOW→

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 DreamLolita 6 211
2 KrK 6 235
3 Heltion 6 259
4 krijgertje 6 268
5 Temotoloraia 6 272

Congratulations to the best hackers:

Rank Competitor Hack Count
1 liouzhou_101 81:-35
2 j_peters 29:-16
3 eR6 18:-19
4 tonyli00000 14:-15
5 lollihunter 8:-7
281 successful hacks and 925 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A Sevlll 0:00
B This0is0the0AmShZ 0:02
C DreamLolita 0:03
D xb0nS 0:14
E P.Alizadeh 0:17
F chemthan 1:07

UPD: Editorial is out

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By pikmike, history, 3 months ago, translation, In English,

1334A - Level Statistics

Idea: pikmike

Tutorial
Solution (pikmike)

1334B - Middle Class

Idea: adedalic

Tutorial
Solution (adedalic)

1334C - Circle of Monsters

Idea: BledDest

Tutorial
Solution (Ne0n25)

1334D - Minimum Euler Cycle

Idea: adedalic

Tutorial
Solution (adedalic)

1334E - Divisor Paths

Idea: BledDest

Tutorial
Solution (pikmike)

1334F - Strange Function

Idea: Roms и BledDest

Tutorial
Solution (BledDest)

1334G - Substring Search

Idea: BledDest

Tutorial
Solution (BledDest)

Read more »

 
 
 
 
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By pikmike, history, 3 months ago, translation, In English,

Hello Codeforces!

On Apr/10/2020 17:35 (Moscow time) Educational Codeforces Round 85 (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 Ne0n25 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:

Codeforces and Harbour.Space

Hey Codeforces,

What a crazy month it’s been!

We hope you and your loved ones are taking care of one another and catching up on everything you didn’t have time for on your normal schedules.

We’ve temporarily closed our physical campus and moved our classes online. It’s not as bad as it sounds though — we’ve always known the future is digital, so we were already preparing for this moment. Either way, we’re back.

SPECIAL PRIZE FOR EDU ROUND 85

This digital transformation opens the door to some pretty awesome new opportunities that allow us to get closer to our community, no matter where in the world they are.

That’s why we have a special prize for the next Educational Round, a space in a course of your choice from our Computer Science or Data Science Programs. You’ll be able to study online with us for 1, 2 or 3 weeks under some of the best Data and Computer Scientists in the world, with all fees on us.

The prize will be for the top 3 users who have confirmed their desire to participate in this competition. To sign up for it, leave us your handle in the form below.

Enrollment in the course you will participate in will depend upon the availability of the course, as well as the prerequisites required for that course.

We hope this provides you with extra incentive for the round, and we’re looking forward to seeing some of you soon!

PARTICIPATE

FULL SCHOLARSHIPS FOR BACHELOR’S PROGRAM

On a different note, we’re happy to announce that we’re offering full scholarships for the most talented high school students who want to study in our Computer Science or Data Science Bachelor’s programs at our university.

At the moment, we have two types of scholarships available:

The Full Scholarship. For the best of the best — all tuition costs are covered by the university. Just show up and show us what you’ve got.

The Co-Creator Scholarship. For those who want to help us change education — all tuition costs are covered by the university, and in addition to your studies, you get to help the Harbour.Space team on their mission for 4 hours/day, getting valuable practical experience in the field and working in a team with some of the brightest young professionals in town.

Fill out the form below and we will contact you for the next steps!

FILL OUT FORM

Looking forward to seeing you kick some ass in the next Educational Round, and stay safe!

Best, Harbour.Space University

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 MiFaFaOvO 7 153
2 jiangly 7 195
3 amnesiac_dusk 7 244
4 risujiroh 7 290
5 bmerry 7 310

Congratulations to the best hackers:

Rank Competitor Hack Count
1 greencis 174:-53
2 Java 94:-8
3 hackVerly 55:-2
4 _BadLoser 55:-10
5 TheScrasse 40
2405 successful hacks and 1303 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A Isabella_Vesterbury 0:02
B arknave 0:02
C Siberian 0:03
D Sevlll 0:16
E LJC00118 0:19
F IceWiz 0:31
G 9baka_Cirno 0:25

UPD: Editorial is out

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By pikmike, history, 3 months ago, translation, In English,

1327A - Sum of Odd Integers

Idea: vovuh

Tutorial
Solution (vovuh)

1327B - Princesses and Princes

Idea: BledDest

Tutorial
Solution (pikmike)

1327C - Game with Chips

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

1327D - Infinite Path

Idea: adedalic

Tutorial
Solution (adedalic)

1327E - Count The Blocks

Idea: adedalic

Tutorial
Solution (Roms)

1327F - AND Segments

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

1327G - Letters and Question Marks

Idea: BledDest

Tutorial
Solution (BledDest)

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By pikmike, history, 3 months ago, translation, In English,

Hello Codeforces!

On Mar/23/2020 17:35 (Moscow time) Educational Codeforces Round 84 (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 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 Ne0n25 Mescheryakov and me. Also huge thanks to Mike MikeMirzayanov Mirzayanov for great systems Polygon and Codeforces.

Good luck to all the participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 MiFaFaOvO 7 230
2 Volkov_Ivan 7 272
3 Egor 7 343
4 2829908231 7 360
5 rainboy 7 707

Congratulations to the best hackers:

Rank Competitor Hack Count
1 theStaticMind 14:-8
2 Chrollo_Lucifer 5:-1
3 Learner 10:-13
4 RitikBaid 3
5 Ashiok 4:-3
139 successful hacks and 617 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A fextivity 0:01
B Sonechko 0:05
C Isaunoya 0:05
D MiFaFaOvO 0:10
E Medeowex 0:11
F YangDavid 0:35
G rainboy 0:44

UPD: Editorial is out

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By pikmike, history, 4 months ago, translation, In English,

1312A - Two Regular Polygons

Idea: BledDest

Tutorial
Solution (vovuh)

1312B - Bogosort

Idea: Roms

Tutorial
Solution (Roms)

1312C - Adding Powers

Idea: adedalic

Tutorial
Solution 1 (adedalic)
Solution 2 (adedalic)

1312D - Count the Arrays

Idea: BledDest

Tutorial
Solution (BledDest)

1312E - Array Shrinking

Idea: MikeMirzayanov

Tutorial
Solution (adedalic)

1312F - Attack on Red Kingdom

Idea: BledDest

Tutorial
Solution (BledDest)

1312G - Autocompletion

Idea: adedalic and BledDest

Tutorial
Solution (BledDest)

Read more »

 
 
 
 
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By pikmike, history, 4 months ago, translation, In English,

Hello Codeforces!

On Mar/09/2020 17:35 (Moscow time) Educational Codeforces Round 83 (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 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 Ne0n25 Mescheryakov and me. Also huge thanks to Mike MikeMirzayanov Mirzayanov for great systems Polygon and Codeforces.

Good luck to all the participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 kefaa2 7 135
2 MiFaFaOvO 7 145
3 neal 7 161
4 uwi 7 191
5 CWOI 7 196

Congratulations to the best hackers:

Rank Competitor Hack Count
1 MarcosK 134:-15
2 _apurv_ 28
3 racsosabe 24:-1
4 sv_restart 18:-3
5 Norrius 16
773 successful hacks and 620 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A hochesh 0:00
B Kirill22 0:02
C i.e 0:03
D neal 0:08
E andrew 0:09
F MiFaFaOvO 0:33
G gisp_zjz 0:31

UPD: Editorial is out

Read more »

 
 
 
 
  • Vote: I like it
  • +207
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By pikmike, history, 5 months ago, translation, In English,

1303A - Erasing Zeroes

Idea: Roms

Tutorial
Solution (Roms)

1303B - National Project

Idea: adedalic

Tutorial
Solution (adedalic)

1303C - Perfect Keyboard

Idea: Roms

Tutorial
Solution (Ne0n25)

1303D - Fill The Bag

Idea: Roms

Tutorial
Solution (Roms)

1303E - Erase Subsequences

Idea: adedalic

Tutorial
Solution (adedalic)

1303F - Number of Components

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

1303G - Sum of Prefix Sums

Idea: Ne0n25

Tutorial
Solution (BledDest)

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  • Vote: I like it
  • +89
  • Vote: I do not like it

By pikmike, history, 5 months ago, translation, In English,

Hello Codeforces!

On Feb/12/2020 17:35 (Moscow time) Educational Codeforces Round 82 (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 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 Ne0n25 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:

Hello Muscat

Hi Codeforces!

This is not the last call for participation, but we’re almost there. We have extended the early bird discount deadline of Hello Muscat ICPC Programming Bootcamp until this Sunday, February 16th. Remember you can request a support letter to present to your university, employer or local companies to sponsor your participation and trip to the bootcamp.

Register now

We would also like to remind you that if your team is going to the ICPC World Finals in Moscow this June, you can fill out the form below to see if you are eligible for a full scholarship for our Bootcamp (flights not included), and we will contact you within three days to let you know about the results.

Fill out form

UPD: There will be 7 problems in the round

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 tmwilliamlin168 7 294
2 Egor 6 173
3 ivan100sic 6 174
4 neal 6 175
5 kefaa2 6 179

39 successful hacks and 147 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A Muhammad_Hokimiyon 0:01
B icecuber 0:04
C MylnikovNikolay 0:09
D waynetuinfor 0:11
E Mehrdad_Sohrabi 0:17
F wucstdio 1:10
G arknave 0:49

UPD: Editorial is out

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  • Vote: I like it
  • +167
  • Vote: I do not like it

By pikmike, history, 5 months ago, translation, In English,

1295A - Display The Number

Idea: adedalic

Tutorial
Solution (BledDest)

1295B - Infinite Prefixes

Idea: Roms

Tutorial
Solution (adedalic)

1295C - Obtain The String

Idea: Roms

Tutorial
Solution (Roms)

1295D - Same GCDs

Idea: adedalic

Tutorial
Solution (adedalic)

1295E - Permutation Separation

Idea: adedalic

Tutorial
Solution (adedalic)

1295F - Good Contest

Idea: Roms

Tutorial
Solution (BledDest)

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  • Vote: I like it
  • +106
  • Vote: I do not like it

By pikmike, history, 5 months ago, translation, In English,

Hello Codeforces!

On Jan/29/2020 17:35 (Moscow time) Educational Codeforces Round 81 (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 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 Ne0n25 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:

Hello Muscat

Hi Codeforces!

As a special prize for the Educational Round 81, we would like to invite the top participants to take part in our Hello Muscat ICPC Programming Bootcamp, which will take place in Oman, from March 19 to March 25, 2020. The prize will cover the participation fee, accommodation, and half-board meals for the entire duration of the bootcamp (except flights)!

There are three requirements to satisfy:

  • You took part in at least 10 rated contests on Codeforces
  • Your max rating should be less than 2400
  • You should be eligible for ICPC and/or IOI 2020+
Fill out the form→

Good luck to everyone!

We are also excited to announce that we are working with our partners to provide free participation (flights not included) for the teams going to the ICPC World Finals 2020, which will take place in Moscow. If you and your team qualified for the Finals, fill out the form below to see if you’re eligible.

Apply Now→

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 nickluo 6 177
2 KrK 6 184
3 NoLongerRed 6 185
4 Anadi 6 200
5 neal 6 204

Congratulations to the best hackers:

Rank Competitor Hack Count
1 GiantTornado 58
2 rachit_raj 51:-1
3 harshraj22 41:-5
4 Ahmad__ 35:-1
5 _sad_ 33:-2
1096 successful hacks and 873 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A antontrygubO_o 0:01
B neal 0:05
C IgorI 0:07
D NoLongerRed 0:06
E A_Fan_of_the_AK_King--lk 0:14
F Combi 0:23

UPD: Editorial is out

Read more »

 
 
 
 
  • Vote: I like it
  • +67
  • Vote: I do not like it

By pikmike, history, 6 months ago, translation, In English,

1288A - Deadline

Idea: adedalic

Tutorial
Solution (adedalic)

1288B - Yet Another Meme Problem

Idea: Roms

Tutorial
Solution (Roms)

1288C - Two Arrays

Idea: BledDest

Tutorial
Solution (Roms)

1288D - Minimax Problem

Idea: BledDest

Tutorial
Solution (BledDest)

1288E - Messenger Simulator

Idea: Ne0n25

Tutorial
Solution 1 (pikmike)
Solution 2 (pikmike)
Solution 3 (pikmike)

1288F - Red-Blue Graph

Idea: BledDest

Tutorial
Solution (BledDest)

Read more »

 
 
 
 
  • Vote: I like it
  • +72
  • Vote: I do not like it

By pikmike, history, 6 months ago, translation, In English,

Hello Codeforces!

On Jan/14/2020 17:35 (Moscow time) Educational Codeforces Round 80 (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 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 Ne0n25 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:

Hello Muscat

Hi Codeforces!

As a special prize for the Educational Round 80, we would like to invite the top 3 participants to take part in our Hello Muscat ICPC Programming Bootcamp, which will take place in Oman, from March 19 to March 25, 2020. The prize will cover the participation fee, accommodation, and half-board meals for the entire duration of the bootcamp (except flights)!

There are three requirements to satisfy:

  • You took part in at least 10 rated contests on Codeforces
  • Your max rating should be less than 2400
  • You should be eligible for ICPC and/or IOI 2020+
Fill out the form→

Good luck to everyone!

Note: If you really want to participate, but cannot afford the participation fee, get in touch with us to request a supporting letter for you to show to your university, employer, or local companies. With this letter, you are opening the possibility of being sponsored by them to attend the bootcamp.

Please fill out this form and we’ll send you the support letter within 3 days!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 isaf27 6 150
2 FSTForces 6 167
3 jiangly 6 178
4 ko_osaga 6 179
5 jhnan917 6 184

Congratulations to the best hackers:

Rank Competitor Hack Count
1 surung9898 59:-2
2 ya_ne_xoxol_ya_kiborg 35:-1
3 B2ej5SjC 30
4 spectre_1502 21:-1
5 Dilemma27 20:-4
434 successful hacks and 746 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A okwedook 0:01
B neal 0:04
C ko_osaga 0:06
D RUSH_D_CAT 0:07
E peach 0:17
F jiangly 1:13

UPD: The editorial is out

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  • +210
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By pikmike, history, 6 months ago, translation, In English,

1279A - New Year Garland

Idea: BledDest

Tutorial
Solution (Roms)

1279B - Verse For Santa

Idea: Roms

Tutorial
Solution (Roms)

1279C - Stack of Presents

Idea: Roms

Tutorial
Solution (Roms)

1279D - Santa's Bot

Idea: BledDest

Tutorial
Solution (Ne0n25)

1279E - New Year Permutations

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

1279F - New Year and Handle Change

Idea: vovuh

Tutorial
Solution (vovuh)

Read more »

Tutorial of div2 B-C #1
 
 
 
 
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  • +88
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By pikmike, history, 6 months ago, translation, In English,

Hello Codeforces!

On Dec/27/2019 17:40 (Moscow time) Educational Codeforces Round 79 (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 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 Ne0n25 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:

Hi Codeforces!

Last spots available for Mike Mirzayanov's course Advanced Algorithms and Data Structures, which will take place in Barcelona, from the 6th to 24th of January, 2020.

The course will consist of three weeks of training, 5 training days each week. The program includes daily lectures and practical exercises. It will be quite educational, insightful and entertaining!

Remember, there’s a special price of 1,000 EUR* for all Codeforces users.

* The cost does not include travel or accommodation.

If you’re interested, send us a message at hello@harbour.space and we will guide you through the next steps.

UPD: Editorial is out

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  • +100
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By pikmike, history, 7 months ago, translation, In English,

1278A - Shuffle Hashing

Idea: Ne0n25

Tutorial
Solution 1 (pikmike)
Solution 2 (pikmike)

1278B - A and B

Idea: Roms

Tutorial
Solution (Roms)

1278C - Berry Jam

Idea: MikeMirzayanov

Tutorial
Solution (pikmike)

1278D - Segment Tree

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

1278E - Tests for problem D

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

1278F - Cards

Idea: BledDest

Tutorial
Solution (BledDest)

Read more »

Tutorial of div2 B-C #1
 
 
 
 
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