PikMike's blog

By PikMike, history, 11 days ago, translation, In English,

1238A - Prime Subtraction

Idea: BledDest

Tutorial
Solution (BledDest)

1238B - Kill `Em All

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

1238C - Standard Free2play

Idea: adedalic

Tutorial
Solution (adedalic)

1238D - AB-string

Idea: Roms

Tutorial
Solution (Roms)

1238E - Keyboard Purchase

Idea: Roms

Tutorial
Solution (Roms)

1238F - The Maximum Subtree

Idea: Roms

Tutorial
Solution (Roms)

1238G - Adilbek and the Watering System

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

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  • Vote: I like it
  • +35
  • Vote: I do not like it

By PikMike, history, 13 days ago, translation, In English,

Hello Codeforces!

On Oct/08/2019 17:35 (Moscow time) Educational Codeforces Round 74 (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 Codeforces,

First of all, thank you for the great feedback on our survey from the last Educational Round. Over 300 people participated, and we hope to start implementing some of your suggestions really soon.

We also wanted to let you know that we have extended the deadline for our fully-funded scholarships for Masters programs in Bangkok.

Remember, they cover the entire tuition fee as well as the cost of living expenses, so If you or someone you know are interested in technology, entrepreneurship, or design, and believe you have what it takes, we want to hear from you!

APPLY HERE→

Last, but not least, we would like to recommend an article published in our blog last week about the “Top 5 Soft Skills Every Developer Has to Have”. What do you think, do you agree with this list?

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 HIR180 7 296
2 9623 7 317
3 stasio6 7 350
4 sigma425 7 400
5 jiangly 7 405

Congratulations to the best hackers:

Rank Competitor Hack Count
1 kimbj0709 120:-19
2 Astaa 107:-111
3 baluteshih 48:-9
4 galen_colin 40:-3
5 Rian_5900 34:-13
571 successful hacks and 641 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A algo.code 0:00
B L4U 0:04
C OmegaLUL229 0:17
D MarcosK 0:08
E GyojunYoun 0:09
F ksun48 0:29
G NotNight 0:51

UPD: Editorial is out

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  • Vote: I like it
  • +55
  • Vote: I do not like it

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

1221A - 2048 Game

Idea: Roms

Tutorial
Solution (Roms)

1221B - Knights

Idea: BledDest

Tutorial
Solution (PikMike)

1221C - Perfect Team

Idea: Roms

Tutorial
Solution 1 (BledDest)
Solution 2 (PikMike)

1221D - Make The Fence Great Again

Idea: Roms

Tutorial
Solution (Roms)

1221E - Game With String

Idea: Roms

Tutorial
Solution (Roms)

1221F - Choose a Square

Idea: Ne0n25

Tutorial
Solution (Ne0n25)

1221G - Graph And Numbers

Idea: BledDest

Tutorial
Solution (BledDest)

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  • Vote: I like it
  • +62
  • Vote: I do not like it

By PikMike, history, 4 weeks ago, In English,

First of all, I'm really sorry for the issues the round had. We paid not enough attention to make sure everything works as intented and got punished for it. That was a lesson for us, we'll do our best to keep the future rounds as clean as possible.

The problem B had an issue with the checker, solutions have been recieving wrong verdicts. Unfortunately, neither its author, nor reviewers have noticed the bug.

Can you spot it without looking in comments?

The bugged checker

It's been compiling with no warnings even with -Wall -Wextra -Wconversion flags. By no means that justifies our carelessness but the mistake was really unfortunate.

We really hope you enjoyed the problems nevertheless.

The contest will definitely be unrated for the participants affected by it.

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  • Vote: I like it
  • +151
  • Vote: I do not like it

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

Hello Codeforces!

On Sep/19/2019 17:35 (Moscow time) Educational Codeforces Round 73 (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:

Hello Codeforces,

We want to know what you think about Harbour.Space’s involvement in the Codeforces community, and how you believe we can improve.

So we created this short, 5 question survey to hear your thoughts about how we can provide you with more stuff that you’re interested in, so that we can improve your experience on Codeforces.

We really value your feedback, so it would mean a lot if you could take a minute and fill out the survey. Thanks in advance!

GO TO SURVEY→

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 kefaa2 7 192
2 jiangly 6 152
3 betrue12 6 187
4 I_love_Tanya_Romanova 6 196
5 pekempey 6 198

Congratulations to the best hackers:

Rank Competitor Hack Count
1 achi_basadzishvili 129:-46
2 apoorv024 87:-4
3 Kolo_Ray7 73:-31
4 lollihunter 52:-7
5 badmofo21 15:-1
544 successful hacks and 568 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A Chereshnya_ 0:01
B Chereshnya_ 0:02
C YahiaAshraf74 0:04
D sysjuruo 0:08
E kefaa2 0:31
F Benq 0:35
G Benq 1:02

UPD: Post about the issue

UPD2: Editorial is out

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  • Vote: I like it
  • -168
  • Vote: I do not like it

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

1217A - Creating a Character

Tutorial
Solution (adedalic)

1217B - Zmei Gorynich

Idea: Roms

Tutorial
Solution (Roms)

1217C - The Number Of Good Substrings

Idea: Roms

Tutorial
Solution (Roms)

1217D - Coloring Edges

Idea: BledDest

Tutorial
Solution (Roms)

1217E - Sum Queries?

Idea: BledDest

Tutorial
Solution (PikMike)

1217F - Forced Online Queries Problem

Idea: BledDest

Tutorial
Solution (PikMike)

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  • Vote: I like it
  • +94
  • Vote: I do not like it

By PikMike, 7 weeks ago, translation, In English,

Hello Codeforces!

On Sep/05/2019 17:35 (Moscow time) Educational Codeforces Round 72 (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 Codeforces,

Harbour.Space University and UTCC are collaborating to offer graduate students from anywhere in the world a once in a lifetime opportunity: fully funded scholarships for our Masters programs in Bangkok.

These scholarships are designed to completely eliminate the barrier between exceptional talents and sophisticated education: they cover the entire tuition fee as well as the cost of living expenses, and furthermore, they provide the student the valuable experience of both studying and working at Harbour.Space University.

We’re looking for the people who are going to change the world.

If you or someone you know are interested in technology, entrepreneurship, or design, and believe you have what it takes, we want to hear from you!

APPLY HERE→

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Tropical_maid 6 212
2 Return.Hao 6 246
3 xyz100 6 272
4 YangDavid 6 280
5 Lawali 6 300

Congratulations to the best hackers:

Rank Competitor Hack Count
1 VegetableP 116:-14
2 Princ_iple 49:-1
3 racsosabe 42:-1
4 shurongwang 36
5 Megatron_99 29:-1
1432 successful hacks and 1595 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A xyz100 0:02
B Chereshnya_ 0:06
C Florin29 0:06
D IgorI 0:08
E Aria 0:30
F 2-SAD 0:51

UPD: The editorial is out

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  • Vote: I like it
  • +131
  • Vote: I do not like it

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

1207A - There Are Two Types Of Burgers

Idea: BledDest

Tutorial
Solution (Roms)

1207B - Square Filling

Idea: BledDest

Tutorial
Solution (BledDest)

1207C - Gas Pipeline

Idea: adedalic

Tutorial
Solution (adedalic)

1207D - Number Of Permutations

Idea: Roms

Tutorial
Solution (Roms)

1207E - XOR Guessing

Idea: adedalic, Ne0n25, BledDest

Tutorial
Solution (BledDest)

1207F - Remainder Problem

Idea: BledDest

Tutorial
Solution (BledDest)

1207G - Indie Album

Idea: adedalic

Tutorial
Solution (PikMike)

Read more »

 
 
 
 
  • Vote: I like it
  • +119
  • Vote: I do not like it

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

Hello Codeforces!

On Aug/22/2019 17:35 (Moscow time) Educational Codeforces Round 71 (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 participants!

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

Hello Codeforces,

We are opening a new campus in Bangkok, Thailand!

We are delighted to introduce a strategic partnership between Harbour.Space University and the University of the Thai Chamber of Commerce – a collaborative effort powered by B.Grimm.

After 3 years of successfully disrupting education in Barcelona, with a unique educational model founded on active learning in entrepreneurship, technology, and design, as well as the most extraordinary academic and professional community on the planet to show for it, we are ready to bring the revolution to our new campus in Bangkok, Thailand.

Scholarships for our Bangkok campus are designed to completely eliminate the barrier between exceptional talents and sophisticated education: they cover the entire tuition fee as well as the cost of living expenses, and furthermore, they provide the student the valuable experience of both studying and working at Harbour.Space University.

Unique opportunities reserved for the most brilliant students from anywhere in the world, our scholarships are more than financial support – they are portals from your past to your future.

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 HERE→

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 hehezhou 7 235
2 pekempey 7 235
3 TadijaSebez 7 238
4 Barichek 7 241
5 ixy 7 247

467 successful hacks and 688 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A V--gLaSsH0ldEr593--V 0:01
B Dalgerok 0:04
C kmjp 0:12
D pizzadelivery 0:13
E AkshajK 0:10
F AnotherRound 0:07
G danya.smelskiy 0:26

UPD: Editorial is out

Read more »

 
 
 
 
  • Vote: I like it
  • +258
  • Vote: I do not like it

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

1202A - You Are Given Two Binary Strings...

Idea: adedalic

Tutorial
Solution (adedalic)

1202B - You Are Given a Decimal String...

Idea: adedalic

Tutorial
Solution (adedalic)

1202C - You Are Given a WASD-string...

Idea: adedalic

Tutorial
Solution (adedalic)

1202D - Print a 1337-string...

Idea: Roms

Tutorial
Solution (Roms)

1202E - You Are Given Some Strings...

Idea: Roms

Tutorial
Solution (adedalic)

1202F - You Are Given Some Letters...

Idea: adedalic

Tutorial
Solution (PikMike)

Read more »

 
 
 
 
  • Vote: I like it
  • +187
  • Vote: I do not like it

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

Hello Codeforces!

On Aug/07/2019 17:35 (Moscow time) Educational Codeforces Round 70 (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 participants!

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

Hello Codeforces!

Ready to get deep?

Take a minute and ask yourselves — what skills are I missing, that I would love to have? What are those key qualities that would take me from being a decent developer to an extraordinary one? Am I where I want to be, in terms of personal progress?

At Harbour.Space, we focus on the key technical and social requirements of the jobs of the future. Our three-week courses are designed for students to acquire and develop specific skills through seminars, workshops, projects, and case studies in a very short amount of time.

Mike Mirzayanov’s course, Advanced Algorithms and Data Structures, is a great example of this:

This, in combination with our unique academic environment, extensive professional network, and our seaside campus in the beautiful city of Barcelona, provides for a truly unique learning experience.

Interested?

Fill out the form below, get more information, and see how you can come attend Mike’s course to see what all the fuss is about!

APPLY HERE→

See you soon!

Harbour.Space

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 esbee 6 258
2 tfg 6 302
3 Heltion 6 310
4 jiangly 6 338
5 Geothermal 5 195

109 successful hacks and 290 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A nantf 0:03
B Denverjin 0:11
C Geothermal 0:20
D dhxh 0:10
E lqs2015 0:19
F duxing201606 0:59

UPD: Editorial is out

Read more »

 
 
 
 
  • Vote: I like it
  • -198
  • Vote: I do not like it

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

1197A - DIY Wooden Ladder

Idea: adedalic

Tutorial
Solution (adedalic)

1197B - Pillars

Idea: BledDest

Tutorial
Solution (BledDest)

1197C - Array Splitting

Idea: Roms

Tutorial
Solution (Roms)

1197D - Yet Another Subarray Problem

Idea: BledDest

Tutorial
Solution (Roms)

1197E - Culture Code

Idea: adedalic

Tutorial
Solution (adedalic)

1197F - Coloring Game

Idea: BledDest

Tutorial
Solution (BledDest)

Read more »

 
 
 
 
  • Vote: I like it
  • +68
  • Vote: I do not like it

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

Hello Codeforces!

On Jul/22/2019 17:35 (Moscow time) Educational Codeforces Round 69 (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 participants!

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

Hello Codeforces!

We hope your summer is going well!

Last Friday we finished the second edition of the Tech Scouts Summer Camp, with 70 participants, 20 different nationalities and many solved problems. We had 6 participants with a full scholarship thanks to the collaboration between Harbour.Space and Codeforces and we are working on increasing this number next year.

We would also like to remind you that we offer scholarships for our technical programmes, such as Computer Science, Data Science and Cyber Security.

They are set in such a way that doesn’t require additional applications — we believe in merit and potential, and so what you put in your application to the university will be our criteria.

You could be just the diamond we’re looking for, but you’ll never know unless you apply!

APPLY HERE→

UPD2: There will be 6 problems in the contest.

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Um_nik 6 111
2 Golovanov399 6 174
3 PinkRabbit 6 190
4 dreamoon_love_AA 6 198
5 _twilight 6 232
6 HIR180 6 252

Congratulations to the best hackers:

Rank Competitor Hack Count
1 greencis 122:-29
2 Ali_Zaiback 26
3 racsosabe 22:-7
4 plusplus6408 14
5 Flamire 14:-3
6 crvineeth97 13:-2
397 successful hacks and 420 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A dorijanlendvaj 0:01
B Um_nik 0:04
C beefman 0:06
D Um_nik 0:12
E Benq 0:11
F Um_nik 0:31

UPD3: Editorial is out

Read more »

 
 
 
 
  • Vote: I like it
  • +172
  • Vote: I do not like it

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

1194A - Remove a Progression

Idea: adedalic

Tutorial
Solution (adedalic)

1194B - Yet Another Crosses Problem

Idea: MikeMirzayanov

Tutorial
Solution (PikMike)

1194C - From S To T

Idea: Roms

Tutorial
Solution (Roms)

1194D - 1-2-K Game

Idea: adedalic

Tutorial
Solution (adedalic)

1194E - Count The Rectangles

Idea: adedalic

Tutorial
Solution (Roms)

1194F - Crossword Expert

Idea: adedalic

Tutorial
Solution (adedalic)

1194G - Another Meme Problem

Idea: Vovuh

Tutorial
Solution (BledDest)

Read more »

 
 
 
 
  • Vote: I like it
  • +83
  • Vote: I do not like it

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

Hello Codeforces!

On Jul/14/2019 17:45 (Moscow time) Educational Codeforces Round 68 (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 participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Benq 7 347
2 Geothermal 6 120
3 tmwilliamlin168 6 168
4 neal 6 174
5 square1001 6 174

Congratulations to the best hackers:

Rank Competitor Hack Count
1 algmyr 8:-4
2 Half-Blood_Prince 3:-1
3 A_Egon_ 2
4 plusplus6408 2
5 Benq 2:-1
47 successful hacks and 344 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A dorijanlendvaj 0:01
B MesyuraTheOldDumbGoblin 0:04
C aneesh2312 0:04
D Benq 0:09
E Denisov 0:21
F Benq 0:15
G ecnerwala 1:07

UPD: Editorial is out

Read more »

 
 
 
 
  • Vote: I like it
  • +227
  • Vote: I do not like it

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

1187A - Stickers and Toys

Idea: MikeMirzayanov

Tutorial
Solution (adedalic)

1187B - Letters Shop

Idea: MikeMirzayanov

Tutorial
Solution (PikMike)

1187C - Vasya And Array

Idea: Roms

Tutorial
Solution (Roms)

1187D - Subarray Sorting

Idea: Roms

Tutorial
Solution (Roms)

1187E - Tree Painting

Idea: BledDest

Tutorial
Solution (Vovuh)
Alternative solution (PikMike)

1187F - Expected Square Beauty

Idea: Roms and adedalic

Tutorial
Solution (adedalic)

1187G - Gang Up

Idea: BledDest

Tutorial
Solution (BledDest)

Read more »

 
 
 
 
  • Vote: I like it
  • +105
  • Vote: I do not like it

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

Hello Codeforces!

On Jun/30/2019 17:45 (Moscow time) Educational Codeforces Round 67 (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 participants!

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Radewoosh 7 220
2 kefaa2 7 346
3 wxhtxdy 6 120
4 square1001 6 136
5 HIR180 6 153

Congratulations to the best hackers:

Rank Competitor Hack Count
1 2014CAIS01 76:-1
2 prateek2112 50:-1
3 takumi152 32:-2
4 Holland_Pig 28
5 sysjuruo 37:-24
1268 successful hacks and 1683 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 arknave 0:02
C HIR180 0:06
D RUSH_D_CAT 0:22
E Noam527 0:06
F zhoutb 0:28
G Luma 0:46

UPD: Editorial is out

Read more »

 
 
 
 
  • Vote: I like it
  • +308
  • Vote: I do not like it

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

1175A - From Hero to Zero

Idea: Roms

Tutorial
Solution (Roms)

1175B - Catch Overflow!

Idea: PikMike

Tutorial
Solution (PikMike)

1175C - Electrification

Idea: adedalic

Tutorial
Solution (adedalic)

1175D - Array Splitting

Idea: adedalic

Tutorial
Solution (Roms)

1175E - Minimal Segment Cover

Idea: adedalic

Tutorial
Solution 1 (PikMike)
Solution 2 (PikMike)

1175F - The Number of Subpermutations

Idea: Roms

Tutorial
Solution (Roms)

1175G - Yet Another Partiton Problem

Idea: adedalic

Tutorial
Solution (adedalic)

Read more »

 
 
 
 
  • Vote: I like it
  • +76
  • Vote: I do not like it

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

Hello Codeforces!

On Jun/05/2019 17:35 (Moscow time) Educational Codeforces Round 66 (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 participants!

UPD:

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

Codeforces! What is the next step in your development?

We understand all about doing things by yourself — after all, we are a startup university, and our student body is exceptional in part because of it’s made up of people who didn’t wait for anyone to show them the way.

If this is you, you belong at Harbour.Space. The purpose of our University is to create a global community of these kinds of people, regardless of age or nationality, because when you’re working by yourself, you can change for the better, but when you work with others, you can change the world.

If you believe you have what it takes, we want you!

The curriculum is part of what makes the modules so special, and the other half? Our outstanding teachers who are leaders in their own respective industries.

Our scholarships are set in such a way that doesn’t require additional applications — we believe in merit and potential, and so what you put in your application to the university will be our criteria.

You could be just the diamond we’re looking for, but you’ll never know unless you apply!

APPLY NOW→

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 mango_lassi 6 145
2 E869120 6 148
3 kefaa2 6 154
4 egor.lifar 6 154
5 Aria 6 157

Congratulations to the best hackers:

Rank Competitor Hack Count
1 Radewoosh 97:-19
2 test_hack 56:-37
3 alvinvaja 30:-10
4 AryaKnight 48:-48
5 nikolapesic2802 30:-14
779 successful hacks and 1077 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 mango_lassi 0:05
C nuip 0:07
D Yushen 0:04
E Sehnsucht 0:20
F osaaateiasavtnl. 0:05
G LgndryGrandmasturbator 0:47

UPD: The editorial is out

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  • Vote: I like it
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By PikMike, history, 5 months ago, translation, In English,

1167A - Telephone Number

Idea: Roms

Tutorial
Solution (Roms)

1167B - Lost Numbers

Idea: Vovuh

Tutorial
Solution (BledDest)

1167C - News Distribution

Idea: MikeMirzayanov

Tutorial
Solution (BledDest)
Solution (PikMike)

1167D - Bicolored RBS

Idea: adedalic

Tutorial
Solution (adedalic)

1167E - Range Deleting

Idea: Roms

Tutorial
Solution (Roms)

1167F - Scalar Queries

Idea: adedalic

Tutorial
Solution (adedalic)

1167G - Low Budget Inception

Idea: adedalic

Tutorial
Solution (adedalic)

Read more »

 
 
 
 
  • Vote: I like it
  • +55
  • Vote: I do not like it

By PikMike, 5 months ago, translation, In English,

Hello Codeforces!

On May/15/2019 17:35 (Moscow time) Educational Codeforces Round 65 (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 participants!

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

Hello Codeforces!

We are collaborating with an external sponsor who is offering a unique scholarship opportunity for women who want to study Cybersecurity or Fintech, both for Bachelors and Masters level.

The scholarship includes:

  • An up to $10,000, one-time financial award, paid to the University
  • An all-expenses-paid trip to the EMEA Summit 28-30 October, 2019 in Berlin
  • A Cybersecurity professional to serve as an industry mentor

Apply before May 30th and Harbour.Space will also consider you for a scholarship from our own funds.

Don't miss this chance to study with us in Barcelona!

If you have questions about the scholarship, please contact us at hello@harbour.space!

APPLY HERE→

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Radewoosh 7 174
2 mnbvmar 7 183
3 I_love_Tanya_Romanova 6 119
4 Farhod_Farmon 6 124
5 xiaowuc1 6 142

Congratulations to the best hackers:

Rank Competitor Hack Count
1 algmyr 57:-1
2 mnbvmar 16:-2
3 xavier_cai 11:-1
4 halyavin 10:-3
5 avm 7
291 successful hacks and 306 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 Farhod_Farmon 0:05
C DieOrBreakout 0:04
D nuip 0:10
E Farhod_Farmon 0:23
F ugly2333 0:13
G Dukkha 0:57

UPD: Editorial is out

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  • Vote: I like it
  • +92
  • Vote: I do not like it

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

1156A - Inscribed Figures

Tutorial
Solution (PikMike)

1156B - Ugly Pairs

Tutorial
Solution (PikMike)

1156C - Match Points

Tutorial
Solution (BledDest)

1156D - 0-1-Tree

Tutorial
Solution (BledDest)

1156E - Special Segments of Permutation

Tutorial
Solution (BledDest)

1156F - Card Bag

Tutorial
Solution (Roms)

1156G - Optimizer

Tutorial
Solution (e-maxx)

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  • Vote: I like it
  • +116
  • Vote: I do not like it

By PikMike, 6 months ago, translation, In English,

Hello Codeforces!

On May/01/2019 17:35 (Moscow time) Educational Codeforces Round 64 (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 participants!

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

Hi Codeforces!

Harbour.Space University, the International Tournament of Young Mathematicians (ITYM) and St. Paul International School Barcelona have designed a special online test for high school students, to take place on May 5th at 15.00 CET Time.

You can take part in the online test if all the following conditions are met:

  1. Between the ages of 12 to 18,
  2. Have not graduated from high school
  3. Eligible to take part in IOI/IMO 2020.
Register (before May 3) →

After the test, all participants will get a 20% discount link to attend Tech Scouts, the two-week summer camp we run from the 8th-19th of July in one of Barcelona's leading international schools, St.Paul’s, and the most successful performers will be interviewed and awarded a full tuition waiver to attend the advanced level of the Advanced Technical Track of Tech Scouts.

In order to register for the contest, please fill out this form before May 3rd, 2019.

We would love to see you guys at our camp this year — if you’re interested in joining, or if you just want to know more, just head over to the Tech Scouts website.

UPD: There are some minor issues with one of the problems, we'll use one of lesser-known problems by Maxim Babenko.

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 step_by_step 7 491
2 RimuruTempest 6 270
3 receed 6 280
4 I_love_Tanya_Romanova 6 286
5 dreamoon_love_AA 6 299

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 64:-3
2 WileE.Coyote 39:-23
3 wzw19991105 18:-1
4 FST-OIer 14:-1
5 omaewamoushindeiruuuuuuu 2
153 successful hacks and 180 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A halyavin 0:06
B nuip 0:07
C quailty 0:04
D waynetuinfor 0:11
E step_by_step 0:05
F step_by_step 0:15
G step_by_step 1:22

UPD2: The editorial is out.

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

1155A - Reverse a Substring

Tutorial
Solution (Vovuh)

1155B - Game with Telephone Numbers

Tutorial
Solution (Roms)

1155C - Alarm Clocks Everywhere

Tutorial
Solution (Vovuh)

1155D - Beautiful Array

Tutorial
Solution (PikMike)

1155E - Guess the Root

Tutorial
Solution (adedalic)

1155F - Delivery Oligopoly

Tutorial
Solution (BledDest)

Read more »

 
 
 
 
  • Vote: I like it
  • +78
  • Vote: I do not like it

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

Hello Codeforces!

On Apr/22/2019 17:35 (Moscow time) Educational Codeforces Round 63 (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 participants!

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

Hi Codeforces!

This summer, we want to invite you to Tech Scouts, the two-week summer camp we run from the 8th-19th of July in one of Barcelona's leading international schools, St.Paul’s.

This camp, divided into Creative and Technical tracks, is designed to lay out the foundation of knowledge for high-school students in the fields of technology, mathematics, business and design. Both tracks are taught in English.

We would love to see you guys at our camp this year — if you’re interested in joining, or if you just want to know more, just head over to the Tech Scouts website.

This camp is for anyone passionate about tech or design, so if you know someone who might be interested, be sure to let them know too!

Ps. Don’t wait too long — you still have an early bird discount, but only until May 20th

UPD: The round will contain 6 problems.

Congratulations to the winners:

Rank Competitor Problems Solved Penalty
1 Um_nik 6 111
2 Cinro_9baka 6 207
3 Ilovebxy 6 247
4 ivan100sic 6 249
5 ainta 6 411

Congratulations to the best hackers:

Rank Competitor Hack Count
1 halyavin 292:-18
2 Haunted_Cpp 31
3 WileE.Coyote 30:-4
4 Disappointment 27:-1
5 czasem_tak_trzeba 23
790 successful hacks and 697 unsuccessful hacks were made in total!

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

Problem Competitor Penalty
A iaeyoayao 0:01
B MesyuraTheOldDumbGoblin 0:03
C NeKrasnyj 0:07
D FlyToTheSky 0:07
E Rezwan.Arefin01 0:17
F Um_nik 0:59

UPD: The editorial is out

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