JetBrains's blog

By JetBrains, history, 3 months ago, In English

Hello Codeforces!

We’re absolutely thrilled about the return of the Kotlin Heroes series! Judging by the record-setting number of registrations for Kotlin Heroes: Episode 9, we’re guessing you’ve missed this series as well.

It's great to see new people just getting started with Kotlin already performing well in competitions. The solutions to all eight previous rounds are available for practice purposes here: Episode 1, Episode 2, Episode 3, Episode 4, Episode 5: ICPC Round, Episode 6, Episode 7 and Episode 8

Congratulations to the top three contestants:

A Kotlin Heroes T-shirt and exclusive Kotlin stickers will be awarded to:

These participants have also won branded T-shirts:

We will contact the winners soon to coordinate the delivery of their prizes!

For those who would like to get to know Kotlin better, we invite you to review our Kotlin solutions for the Advent of Code algorithmic puzzles, read our competitive programming tutorial, and watch the videos from our Kotlin in Competitive Programming YouTube playlist.

Good luck and we hope you enjoy Kotlin!

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By JetBrains, history, 2 years ago, In English

Hello Codeforces!

Kotlin Heroes: Episode 8 was the third round of the Kotlin Heroes series in 2021. The “8” from “Kotlin Heroes: Episode 8” symbolizes our infinite respect for all who participated! We are very happy to see new people learn Kotlin and perform brilliantly in the competition. All the previous rounds are available to be used for practice here: Episode 1, Episode 2, Episode 3, Episode 4, Episode 5: ICPC Round, Episode 6, and Episode 7.

Сongratulations to the top three contestants:

A Kotlin Heroes t-shirt and exclusive Kotlin stickers will be presented to:

These participants also won branded t-shirts:

We will contact the winners soon to coordinate the delivery of your prizes!

The Kotlin Heroes: Episode 8 practice round took place during the ICPC World Finals. Gennady “tourist” Korotkevich, a repeat winner of Kotlin Heroes, was solving the practice round tasks during the event opening. We invite you to watch this presentation.

For those who would like to get to know Kotlin better, we invite you to check out Kotlin Basics track on JetBrains Academy, take a look at basic Kotlin, solve Koans in the free course from JetBrains Educational Products, visit Kotlin Playground, check out the tutorial, and these videos on competitive programming in Kotlin.

More information about Kotlin Heroes contests: https://kotlinlang.org/lp/kotlin-heroes/.

We wish you luck and hope you enjoy Kotlin!

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By JetBrains, history, 3 years ago, In English

Hello Codeforces!

The second round of the Kotlin Heroes series in 2021 was a great one! Thanks to the authors and all who participated! We are very happy to see new people among the winners. All the rounds are available to be used for practice here: Episode 1, Episode 2, Episode 3, Episode 4, Episode 5: ICPC Round, Episode 6 and Episode 7.

The “7” from “Kotlin Heroes: Episode 7” was the lucky number for this top three contestants:

  1. Petr
  2. tourist
  3. Maksim1744

A Kotlin Heroes t-shirt and exclusive Kotlin stickers will be presented to:

  1. Petr
  2. tourist
  3. Maksim1744
  4. Tlatoani
  5. Golovanov399
  6. Bench0310
  7. Potassium
  8. eatmore
  9. tabr
  10. SYury
  11. LeoPro
  12. Ra16bit
  13. Jatana
  14. nuip
  15. xiaowuc1
  16. Fortin
  17. pashka
  18. Geothermal
  19. timmyfeng
  20. senjougaharin
  21. PurpleCrayon
  22. TadijaSebez
  23. natsugiri
  24. uwi
  25. Spheniscine
  26. firi.
  27. ngfam
  28. TripleM5da
  29. receed
  30. MagentaCobra
  31. WiwiHo
  32. galen_colin
  33. darkkcyan
  34. Heart_Blue
  35. DANDROZAVR
  36. JettyOller
  37. Kude
  38. thenymphsofdelphi
  39. SecondThread
  40. qpwoeirut
  41. Andreasyan
  42. taran_1407
  43. Moririn2528
  44. insert_cool_handle
  45. Sugar_fan
  46. Dart-Xeyter
  47. clyring
  48. abc864197532
  49. Skypiea
  50. golikovnik

These participants also won branded t-shirts:

  1. post
  2. tongtongac
  3. Roll_Num_56
  4. jakao
  5. Dmitry07
  6. MarekSuchanek
  7. Meliodas
  8. litesam
  9. Reeman
  10. sashamc
  11. eanacra
  12. gustason
  13. zuevmaxim
  14. kadhonn
  15. dayanruben
  16. zubra.bubra
  17. I_love_Avicii
  18. bsav157
  19. EgorkA_82
  20. ZergTricky
  21. rohitkumar0510
  22. a1000
  23. blakelist
  24. fuad720
  25. Tarun_19
  26. vividsky
  27. toilavu
  28. codeash14
  29. TheIceKing
  30. stlouee
  31. Neitex
  32. pkpawan
  33. GkG
  34. denis2010
  35. ramint
  36. NooB_NO_1
  37. ivanilos
  38. ved_07
  39. justaperson.
  40. janicekartika
  41. somerandomaltacc3034
  42. solvemproblr
  43. sigrlinn
  44. godavari9823
  45. vladas88
  46. HanaYukii
  47. alien_hun
  48. HeNeos
  49. nhanquyentran1
  50. leekc

We will contact the winners soon to coordinate the delivery of your prizes!

For those who would like to get to know Kotlin better, we invite you to take a look at basic Kotlin, solve Koans in the free course from JetBrains Educational Products, visit Kotlin Playground, check out the tutorial, and these videos on competitive programming in Kotlin.

We wish you all the best and hope you enjoy coding with Kotlin!

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By JetBrains, history, 3 years ago, translation, In English

Hello Codeforces!

The sixth round of the Kotlin Heroes series recently finished! All the rounds are available to be used for practice here: Episode 1, Episode 2, Episode 3, Episode 4, Episode 5: ICPC Round and Episode 6). Thanks to everyone who participated – you inspire us to work even harder on the problems for the next round, and we think you’re really going to like them!

Congratulations to the top three contestants:

  1. tourist
  2. Egor
  3. Tlatoani

A Kotlin Heroes t-shirt and exclusive Kotlin stickers will be presented to:

  1. tourist
  2. Egor
  3. Tlatoani
  4. eatmore
  5. uwi
  6. Benq
  7. Geothermal
  8. TadijaSebez
  9. JettyOller
  10. Maksim1744
  11. pashka
  12. Sugar_fan
  13. dalt
  14. galen_colin
  15. tabr
  16. SYury
  17. natsugiri
  18. Golovanov399
  19. Spheniscine
  20. taran_1407
  21. Ra16bit
  22. Aidos
  23. yudedako
  24. nuip
  25. knightL
  26. golikovnik
  27. wifiiii
  28. Fortin
  29. majk
  30. WiwiHo
  31. Bench0310
  32. wu_qing
  33. Kuyan
  34. Nikitosh
  35. cjtoribio
  36. receed
  37. vadimmm
  38. SecondThread
  39. LeoPro
  40. rapira
  41. -14
  42. nhho
  43. PavelKunyavskiy
  44. abc864197532
  45. tatyam
  46. Heart_Blue
  47. Ji_Kuai
  48. darnley
  49. Potassium
  50. 353cerega

These participants also won branded t-shirts:

  1. polingram
  2. Prateek
  3. rotavirus
  4. linjek
  5. pr3pony
  6. ostroumov
  7. harshrajani460
  8. xiaowuc1
  9. arvindf232
  10. illyakr
  11. Jetman
  12. Leksiq
  13. IceKnight1093
  14. procrastinate7
  15. man.yasakov
  16. Viktor36
  17. matvey.kazakov
  18. cmplx-xyttmt
  19. SourabhYelluru
  20. daisy_2000
  21. stanm
  22. cristian1997
  23. SerVB
  24. aaronsms
  25. chick_magnet
  26. Ditmarscehen
  27. My_password_is_qwerty123
  28. Misha_Help
  29. sohsoh
  30. igla
  31. ans_human
  32. mystic777
  33. __RANI
  34. CM_when
  35. MissNick
  36. MrArpit
  37. penad
  38. XAXAEBATb
  39. son8bon
  40. RandYan
  41. adimiclaus15
  42. babkabass
  43. KKT_89
  44. nishuz
  45. BMking
  46. KEKWait
  47. Kerpoo
  48. pineapple_pasta
  49. GlobalElite
  50. aka2910

We will contact the winners soon to coordinate the delivery of your prizes!

Special thanks goes to SecondThread for streaming the solutions of the entire practice round. Check out this wonderful tutorial: https://codeforces.com/stream/203

If you are still new to Kotlin but want to give it your all in the next round, take a look at Basic Kotlin (solve Koans), Kotlin Playground, this tutorial, and these videos on competitive programming in Kotlin.

We wish you all the best and hope you enjoy coding with Kotlin!

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By JetBrains, history, 3 years ago, In English

Hello Codeforces!

One of the most memorable Kotlin rounds of this year took place just recently. More than 6.7 thousand participants have registered for it. We thank everyone for your interest in Kotlin! Everyone who took part in this round will receive a link to download a personalized online certificate within the next two weeks. Work on this has already started.

Our warm congratulations to the winners of the 1st, 2nd, and 3rd place, who receive cash prizes:

  1. tourist
  2. Benq
  3. Geothermal

A Kotlin Heroes t-shirt and exclusive Kotlin stickers will be presented to:

And also these participants won branded T-shirts:

Finally, the last, but not least, gift for today: ICPC-experience, an invitation to the Moscow World Finals 2021, all-inclusive on-site (hotel, meals, ceremonies, and swag, are included; visa, flights, transportation to the contest location is not).

And a special recognition prize from the ICPC goes to tourist.

If you are still new to Kotlin you could look into a tutorial on competitive programming in Kotlin and watch these videos on competitive programming in Kotlin. Also, all the previous Kotlin Heroes Rounds are available for practice here: Episode 1, Episode 2, Episode 3, Episode 4 and Episode 5: ICPC Round.

We wish you all the best and hope you enjoy Kotlin.

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By JetBrains, 4 years ago, In English

Hello, Codeforces!

First and foremost, we would like to say a massive thank you to everyone who entered and submitted their answers to the first and second Kotlin Heroes competitions which was held previously. Congratulations to the top 3 winners:

Episode 1

  1. Petr
  2. ecnerwala
  3. eatmore

Episode 2

  1. tourist
  2. eatmore
  3. Benq

Ready to challenge yourself to do better? The third "Kotlin Heroes" competition will be hosted on the Codeforces platform on Feb/27/2020 16:35 (Moscow time). The contest will last 2 hours 30 minutes and will feature a set of problems from simple ones, designed to be solvable by anyone, to hard ones, to make it interesting for seasoned competitive programmers. Top three winners will get prizes of $512, $256, and $128 respectively, top 50 will win a Kotlin Heroes t-shirt and an exclusive Kotlin badge, competitors solving at least one problem will enter into a draw for one of 50 Kotlin Heroes t-shirts.

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

  • The round is unrated.
  • The contest will have 6-10 problems of various levels of complexity.
  • You are only allowed to use Kotlin to solve these problems.
  • Participants are ranked according to the number of correctly solved problems. Ties are resolved based on the lowest total penalty time for all problems, which is computed as follows. For each solved problem, a penalty is set to the submission time of that problem (the time since the start of the contest). An extra penalty of 10 minutes is added for each failed submission on solved problems (i.e., if you never solve the problem, you will not be penalized for trying that problem). If two participants solved the same number of problems and scored the same penalty, then those of them who had previously made the last successful submission will be given an advantage in the distribution of prizes and gifts.

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

REGISTER →

If you are still new to Kotlin we have prepared a tutorial on competitive programming in Kotlin and a practice round, where you can try to solve a few simple problems in Kotlin. All the solutions are open, which means that you can look at the solution even if you haven't solved the problem yet. The practice round is available by the link.

We wish you luck and hope you enjoy Kotlin.

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Announcement of Kotlin Heroes: Episode 3
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By JetBrains, 5 years ago, In English

Hello, Codeforces!

First and foremost, we would like to say a massive thank you to everyone who entered and submitted their answers to the first Kotlin Heroes competition which was held back in May. Congratulations to the top 3 winners Petr, ecnerwala, and eatmore on their incredible achievement, especially considering they were up against 4,500 other registrants from over 63 countries. We’d also like to give a shout out to tourist for being the only other person, outside of the top 3, to manage to solve every problem set from this round. Well done all of you!

Ready to challenge yourself to do better? The second "Kotlin Heroes" competition will be hosted on the Codeforces platform on the 7th of September, 2019, at 14:35 UTC (17:35 MSK, 07:35 PDT, 22:35 CST). The contest will last 2 hours 30 minutes and will feature a set of problems from simple ones, designed to be solvable by anyone, to hard ones, to make it interesting for seasoned competitive programmers. Top three winners will get prizes of $512, $256, and $128 respectively, top 50 will win a Kotlin Heroes t-shirt and an exclusive Kotlin badge, competitors solving at least one problem will enter into a draw for one of 50 Kotlin Heroes t-shirts.

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

  • The round is unrated.
  • The contest will have 6-10 problems of various levels of complexity.
  • You are only allowed to use Kotlin to solve these problems.
  • Participants are ranked according to the number of correctly solved problems. Ties are resolved based on the lowest total penalty time for all problems, which is computed as follows. For each solved problem, a penalty is set to the submission time of that problem (the time since the start of the contest). An extra penalty of 10 minutes is added for each failed submission on solved problems (i.e., if you never solve the problem, you will not be penalized for trying that problem). If two participants solved the same number of problems and scored the same penalty, then those of them who had previously made the last successful submission will be given an advantage in the distribution of prizes and gifts.

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

REGISTER →

If you are still new to Kotlin we have prepared a tutorial on competitive programming in Kotlin and a practice round, where you can try to solve a few simple problems in Kotlin. All the solutions are open, which means that you can look at the solution even if you haven't solved the problem yet. The practice round is available by the link.

We wish you luck and hope you enjoy Kotlin.

UPD: Thank you for the participation. The editorials are published.

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Announcement of Kotlin Heroes: Episode 2
Announcement of Kotlin Heroes: Practice 2
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By JetBrains, 5 years ago, In English

Hello, Codeforces!

We are happy to announce that in partnership with Codeforces to promote Kotlin programming language we are launching a series of "Kotlin Heroes" programming contests.

Kotlin programming language was introduced by JetBrains in 2011 and reached its first stable version 1.0 in 2016. The current language version is 1.3.31. The language is focused on solving the needs of application developers in various domains. Kotlin is a statically typed language that is designed for writing concise code, with less ceremony and more substance in it, and to scale from applications of just a few lines long to multi-million-lines projects.

While not being specifically designed for competitive programming, it incidentally fits well in this domain, reducing the typical amount boilerplate that a programmer needs to write and read while working with the code almost to the level offered by dynamically-typed scripting languages, while having tooling and performance of a statically-typed language.

The first "Kotlin Heroes" competition will be hosted at Codeforces platform on May/28/2019 17:35 (Moscow time). The contest will last 2 hours 30 minutes and will feature a set of problems from simple ones, designed to be solvable by anyone, to hard ones, to make it interesting for seasoned competitive programmers. Top three winners will get prizes of $512, $256, and $128 respectively, top 50 will win a Kotlin Heroes t-shirt and an exclusive Kotlin badge, competitors solving at least one problem will enter into a draw for one of 50 Kotlin Heroes t-shirts.

The round is held in accordance with slightly modified ICPC rules:

  • The round is unrated.
  • The contest will have 6-10 problems of various levels of complexity.
  • You are only allowed to use Kotlin to solve these problems.
  • Participants are ranked according to the number of correctly solved problems.
  • Ties are resolved based on the lowest total penalty time for all problems, which is computed as follows. For each solved problem, a penalty is set to the submission time of that problem (the time since the start of the contest). An extra penalty of 10 minutes is added for each failed submission on solved problems (i.e., if you never solve the problem, you will not be penalized for trying that problem).

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

REGISTER →

To help you get familiar with Kotlin we have prepared a tutorial on competitive programming in Kotlin and a practice round, where you can try to solve a few simple problems in Kotlin. All solutions are open, it means that you can look at a solution even if you haven't solved a problem yet. The practice round is available by the link.

We wish you luck and hope you enjoy Kotlin.

UPD 1: Many thanks to the testers elizarov, Benq, cdkrot, nhho, ksun48. Also KAN helped a lot with suggestions to the problems. And to all the participants warm greetings from authors MikeMirzayanov, vovuh, adedalic and pashka — they invented and prepared the problems for you!

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Announcement of Kotlin Heroes: Episode 1
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