By pinely, 5 weeks ago, translation, In English

Hey, Codeforces!

Pinely is here! Just like every year, we are sponsoring the PTZ competitive programming camp. As a part of this, we have prepared a contest for the participants and invite everyone to join it on Codeforces.

Pinely Round 2 (Div. 1 + Div. 2) is scheduled to start on Aug/30/2023 17:35 (Moscow time).

During this round, you will have the opportunity to solve 9 problems within a time frame of 3 hours. The round will be rated for everyone.

The problems have been authored and prepared by the Pinely team: AndreySergunin, ch_egor, Endagorion, amethyst0, zeliboba, zemen along with our special friend Golovanov399.

We would like to express our special thanks to:

We sincerely hope that you enjoy our contest. Wishing you good luck and lots of fun!

P.S. If you are interested in working at Pinely, please visit our website:, send us an email at or fill in the form here


Congratulations to the winners!

  1. tourist
  2. Radewoosh
  3. QAQAutoMaton
  4. jiangly
  5. Ormlis


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By amiya, history, 2 months ago, In English

Hello everyone, we are happy to announce that the 2nd Universal Cup has started officially.

The Universal Cup is a non-profit organization dedicated to offering training resources for competitive programming teams. Our website is (in English and Chinese).

In the previous season, over 750 teams from more than 300 affiliations all over the world, registered and participated in a total of 22 stages, encompassing contests from Asia, Europe, and America.

With the permission of contest setters and without involving copyright disputes, the Universal Cup will hold mirror contests for some undisclosed competition sets. It is expected to hold at least 20 contests in this season. We will simulate the actual situation in the competition, executing the board freeze in the last hour. At the same time, we will provide an overall rating board, which will help the team to make a reasonable assessment of itself.

Over the past few weeks, the committee has worked hard to schedule stages and try to improve the competing experience for participants. We are very excited to share some information here as a head up:

  • In the upcoming 2nd Universal Cup, starting from September 2nd, 2023, we have already scheduled 14 high-quality stages from Asia and Europe mainly. The current schedule can be viewed on the main page of our website

  • There are also 4 stages (expected on October 7th, 14th, 21st, and December 9th) in confirming. The schedule in the second half will also be updated later.

  • We have managed to upgrade our judging system on QOJ, and we will use it as the contest platform starting this season. To provide more flexibility, instead of 3 fixed time windows, teams now can choose to start to compete in one of the following 6 windows as they want:

    • 13:00 (UTC +8) on Saturday ~ 18:00 (UTC +8) on Saturday
    • 16:00 (UTC +8) on Saturday ~ 21:00 (UTC +8) on Saturday
    • 19:00 (UTC +8) on Saturday ~ 24:00 (UTC +8) on Saturday
    • 21:00 (UTC +8) on Saturday ~ 02:00 (UTC +8) on Sunday
    • 23:00 (UTC +8) on Saturday ~ 04:00 (UTC +8) on Sunday
    • 02:00 (UTC +8) on Sunday ~ 07:00 (UTC +8) on Sunday
  • For teams that have already registered, if they have done at least 3 contests in the previous season, their account will be preserved and enrolled into the current season automatically. Otherwise, the same as new teams, please register following the instructions on Registration.

  • The official website has been upgraded. You are able to view all information from the previous by simply choosing the corresponding season on the website.

The first contest will be the stage Qingdao on September 2nd, 2023. The contest source is The 2018 ACM-ICPC Asia Qingdao Regional Online Contest prepared by SUA Problem Setter Team. For a great number of Chinese teams, we believe this will be a good practice to prepare for the upcoming ICPC preliminary online contests in late September.

As well as many other future stages, this stage will be uploaded to Gym afterward. We are grateful to MikeMirzayanov for letting us advertise Universal Cup in Codeforces and providing the great platform Codeforces and Polygon to help prepare contests. We are also very thankful to all contest setters of stages for your support to the Universal Cup. If any setter would like to propose a stage, please feel free to contact us.

Universal Cup Committee:

(Sorted by lexicographical order of the last name)

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By Parisa_Amiri, 6 weeks ago, In English

Salam, Codeforces! $$$\color{white}{\text{ «Be attentive about your thought that becomes your behavior» «Be attentive about your behavior that becomes your speech» «Be attentive about your speech because it becomes your habit»«Be attentive about your habit because it becomes your personality»«Be attentive about your personality because it becomes your destiny» Said by: Imam Ali}}$$$

We're so excited to invite you to take part in our round Harbour.Space Scholarship Contest 2023-2024 (Div. 1 + Div. 2) which will start on Aug/26/2023 17:35 (Moscow time). The round will be rated and open for everyone.

The problems were prepared and authored by amenotiomoi, Psychotic_D, wuhudsm, Parisa_Amiri, chromate00, JohnVictor, ODT, ugly2333, Lavine, RiverHamster, flowerletter and AquaMoon.

We would like to thank :

You will be given $$$9$$$ problems and $$$3$$$ hours to solve!

Score Distribution:


UPD1 : Editorial is out.

UPD2 :

First Solve

Problem Name
A qiuzx
B noimi
D Um_nik
E Geothermal
F MysticPanda
G Radewoosh
H maroonrk
I Radewoosh, One and only Orz

Top Performers

Rank Name
1 Radewoosh
2 maroonrk
3 amiya
4 Benq
5 Um_nik
6 jiangly
8 noimi
9 hos.lyric
10 Brewess

GL & HF ;)

Sign up for the contest →

This round wouldn't have been possible without Harbour.Space University's support.

This contest is for all interested eligible programmers who want to start their bachelor and master studies in Barcelona, Spain or Bangkok, Thailand, and join ICPC team.

For the next academic year (2023/24), Harbour.Space University is recruiting a fascinating community of competitive programmers from the top prize-winners of international Olympiads to join one of several competitive programming teams at the university.

In the next few years, their goal is to continue winning SWERC and competing at a high level in the ICPC globally. Therefore they want to invest a serious amount of energy, resources, and talent into these activities.

That’s why you are invited on an exciting journey in the company of like-minded people, outstanding coaches, and ongoing partnership Harbour.Space University with Codeforces.

Over 100 educational rounds were already organized, so the time has come to test our joint efforts and reward the most diligent.

Here’s what you win if you place in the contest:

Codeforces and Harbour.Space

The monthly living allowance throughout the entire duration of studies may vary depending on the overall performance of the students as measured by their GPA, professional achievements and official ICPC competition results. As a guideline, it is in the range of 700-1500 EUR (it might be applied to the contestants who win 4th-10th places).

No application fee is required for any of the awards listed above.

Good luck, and may the code be with you!

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By diskoteka, 5 weeks ago, translation, In English

☀ ☀ ☀ Hey Codeforces ☀ ☀ ☀

Summer is ending, but my team and I are happy to invite you to participate in Codeforces Round 894 (Div. 3). The round will take place on Aug/24/2023 17:35 (Moscow time). You will be offered 7 problems with expected difficulties to compose an interesting competition for participants with ratings up to 1600. However, all of you who wish to take part and have a rating of 1600 or higher, can register for the round unofficially.

The round will be hosted by rules of educational rounds (extended ICPC). Thus, solutions will be judged on preliminary tests during the round, and after the round, it will be a 12-hour phase of open hacks.

You will be given 7 problems and 2 hours and 15 minutes to solve them.

Note that the penalty for the wrong submission in this round is 10 minutes.

Remember that only the trusted participants of the third division will be included in the official standings table. As it is written by link, this is a compulsory measure for combating unsporting behavior. To qualify as a trusted participant of the third division, you must:

  • take part in at least five rated rounds (and solve at least one problem in each of them)
  • do not have a point of 1900 or higher in the rating.

Regardless of whether you are a trusted participant of the third division or not, if your rating is less than 1600, then the round will be rated for you.

Problems have been created and written by: diskoteka, pavlekn, playerr17. Ivang helped us with the idea of one of the tasks.

We would like to thank:

  1. Vladosiya for coordinating the round

  2. MikeMirzayanov for great Polygon and Codeforces platforms

  3. feeder1, Xellos for red testing

  4. michao, induk_v_tsiane, Phantom_Performer, vladmart, dmkozyrev_thinks_slowly, LordVoIdebug, vrintle for yellow testing

  5. kzyKT, celin for purple testing

  6. ZiXeL, egorsa, MADE_IN_HEAVEN, Thost, Nafis, mewnya, natalina, Serik2003 for blue testing

  7. i_love_penguins, tnaito, akwa_blue, Zeyad_Hekal, NgJaBach for cyan testing

  8. mkshh, myav for green testing

We wish you all good luck and a high rating!

UPD: Editorial published

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

Hello Codeforces!

On Aug/17/2023 17:35 (Moscow time) Educational Codeforces Round 153 (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 Adilbek adedalic Dalabaev, Ivan BledDest Androsov, Maksim Neon Mescheryakov and me. Also, huge thanks to Mike MikeMirzayanov Mirzayanov for great systems Polygon and Codeforces.

Good luck to all the participants!

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


Harbour.Space University has partnered with Giga (Unicef) to offer Master’s degree scholarships in the field of Computer Science and Front-end Development, as well as work experience.

We are looking for various junior to mid level candidates:

Front-end Developer:

This student will work closely with the blockchain developer and product lead to contribute to the design and implementation of user interfaces for the company's blockchain-based prototypes. They will be responsible for translating UI/UX design wireframes into functional and visually appealing web applications, ensuring seamless user experiences. The student will collaborate with blockchain and backend developers and designers to integrate front-end components with server-side logic and optimize application performance. They will also be involved in testing, debugging, and maintaining the front-end codebase. The intern will have the opportunity to gain practical experience in front-end development within the context of blockchain technology and contribute to the Giga’s mission of connecting schools to the internet.

  • Solid understanding of HTML, CSS, and JavaScript
  • Familiarity with front-end frameworks and tools such as React or Vue.js.
  • Strong problem-solving skills, attention to detail, and a passion for creating intuitive user interfaces are essential

Full Stack Developer:

  • Interest and experience in web application development, data products and OpenAPIs
  • Comfortable with on-cloud deployment services (preferably Azure), Git and CI/CD pipeline and deployment processes
  • Experience with open-source projects is highly preferred
  • Strong ML knowledge
  • Experience with data visualization tools like matplotlib, ggplot, d3.js, Tableau that help to visually encode data
  • Excellent communication skills, — it is incredibily important to describe findings to a technical and non-technical audience
  • Strong software engineering background
  • Hands-on experience with data science tools
  • Problem-solving aptitutde
  • Analytical mind and great business sense
  • Degree in computer science, engineering or relevant field is preferred

All successful applicants will be eligible for a 100% tuition fee scholarship (29.900 €/year) provided by the partner company.


Study Commitment: 3 hours/day

You will complete 15 modules (each three weeks long) in one year. Daily class workload is 3 hours, plus homework to complete in your own time.

Work Commitment: 4+ hours/day

Immerse yourself in the professional world during your apprenticeship. You’ll learn from the best and get to apply your newly acquired knowledge in the field from day one.


  • Industry experience
  • International exposure
  • Eager to learn
  • Sustainability is a key topic for you
  • You want to work for an NGO
Apply here →

UPD: Editorial is out

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By pakhomovee, 7 weeks ago, In English

Hello, Codeforces!

We are glad to invite everyone to participate in Codeforces Round 893 (Div. 2), which will be held on Aug/15/2023 17:35 (Moscow time).

Please note the unusual start time of the round. This round will be rated for the participants with rating lower than 2100.

Our round is completely set by SIS (Summer Informatics School) students. We did our best to prepare interesting and creative problems. You can check out some of the previous rounds prepared by SIS students: Codeforces Round 816 (Div. 2), Codeforces Round 815 (Div. 2),Codeforces Round #694,Codeforces Round #612,Codeforces Round #530.

Task authors and developers: Daria arbuzick Grekova, Petr green_gold_dog Losev, Yaroslav Yar_sem Semenyuk, Artem ArtAlex Alexeev, Anton NToneE Egorov, Fedor FedShat Shatokhin, Timofey T4M0FEY Izhitskyi, Egor salyg1n Salygin, Vladimir 1000--7 Gerasikov under the guidance of Evgenii pakhomovee Pakhomov

We are very thankful to

You will have 5 tasks and 2 hours to solve them. We recommend you read all the problems. The contest may contain interactive problems! Make sure to read this post.

The scoring distribution is $$$500-1250-1500-2000-(1750+1000)$$$

Note that the round has been moved one hour later. The contest start time is Aug/15/2023 17:35 (Moscow time)

We hope that you will enjoy our tasks!

Good luck!

UPD: Editorial

UPD 2: Congratulations to the winners!

Div. 2:

  1. dong_liu

  2. yydtq

  3. wfoifysaasisufgv

  4. qwesda

  5. Van_Dijk

Div. 1:

  1. jiangly

  2. neal

  3. BucketPotato

  4. kotatsugame

  5. YocyCraft

First solves:

A. ball_of_wool

B. ecnerwala

C. nigus

D. jiangly

E1. grass8sheep

E2. yydtq

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

Hello, Codeforces.

We are happy to invite you to Codeforces Round 892 (Div. 2), which will take place on Aug/12/2023 17:35 (Moscow time). All of the problems are original and were prepared by a collective of authors, consisting of kristevalex, i_love_penguins, efimovpaul and me, induk_v_tsiane. This round will be rated for participants with a rating lower than 2100.

We would like to thank:

You will be given 6 problems and 2 hours to solve them. The score distribution is 500 — 1000 — 1250 — 1750 — 2250 — 3000.

I would like to also congratulate my cousin Max, who is turning 30 the day of the round. If you wish, you can write birthday wishes for him and I will pass them on.

UPD: Editorial

UPD 2: Congratulations to the winners!

Div. 2:

  1. modulo998244353

  2. botjiaxun

  3. Tmath_OneLove

  4. 1kri

  5. Alihan_8

Div. 1:

  1. Geothermal

  2. heno239

  3. maspy

  4. jiangly

  5. Ormlis

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

Hello, my favorite community!

I’m in a hurry to tell you about a new event from our main sponsor — TON Smart Challenge #4!

An exciting 10 days contest that's open to both beginners and experienced FunC developers with a total prize fund of 30,000 TON begins on August 8th and lasts until August 18th, 23:59:59 UTC+4.

TON Smart Challenge #4 is designed to showcase the fundamental aspects of how smart contracts function in TON. Participants will have the opportunity to master complex cell manipulations, smart contract storage organization, comment handling, basic cryptography, and the logic of governance smart contracts through problem-solving.

TON Smart Challenge 4 →

To enter the challenge, simply register via the @toncontests_bot on Telegram. The bot will guide you through the registration process and keep you informed when the challenge starts, and the tasks are published. It will also help you submit your solutions as a legitimate participant.

More details about the contest and prize distribution one may find on the website.

But that’s not all the news!

In the early days of August was unveiled a new and improved TON Society.

TON Society, community of like-minded people united by the idea to contribute to the development of the TON ecosystem, has adjusted its philosophy and presents its improved version.

The mission of the upgraded community is to develop TON regional communities around the world, help enthusiasts organize offline meetings and attract local investors to work on TON projects.

To make this happen were established hubs in different regions worldwide:

Builders and developers are welcome to join the TON Society and regional hubs.

Participating in TON Society means you’re aligning with the mavericks, forward-thinkers, the game-changers, and those who are shaping the world of TON.

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By Pa_sha, 2 months ago, In English

Hello Codeforces!

We are pleased to invite you all to participate in Codeforces Round 891 (Div. 3), which will start on Aug/07/2023 17:35 (Moscow time).

The format of the event will be like any Div. 3 rounds:

  • 6-8 tasks;

  • ICPC rules with a penalty of 10 minutes for an incorrect submission;

  • 12-hour phase of open hacks after the end of the round (hacks do not give additional points)

  • after the end of the open hacking phase, all solutions will be tested on the updated set of tests, and the ratings recalculated

  • by default, only "trusted" participants are shown in the results table.

We encourage participants with a rating of 1600+ not to create new accounts but to participate unofficially.

Only trusted participants of the third division will be included in the official standings table. This is a forced measure for combating unsporting behavior. To qualify as a trusted participant of the third division, you must:

  • take part in at least five rated rounds (and solve at least one problem in each of them),
  • do not have a point of 1900 or higher in the rating.

Regardless of whether you are a trusted participant of the third division or not, if your rating is less than 1600 (or you are a newcomer/unrated), then the round will be rated for you.

Problems have been created and written by our team: FBI, Skillful_Wanderer, SashaT9 and Pa_sha.

We would like to thank

Good luck!

UPD: There was an error on problem F. We fixed the tests and rejudged solutions . We apologize for that. It only affected a few people whose solutions passes all tests now. Also some hacks were already added to the tests and broke some of solutions.

UPD2: Editorial

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By Vladithur, history, 2 months ago, In English
Hi, Codeforces!

Alexdat2000, Igorfardoc, and I are pleased to invite you to our Codeforces Round 890 (Div. 2) supported by Constructor Institute, which will be held on Aug/05/2023 17:35 (Moscow time). This round will be rated for participants with a rating lower than 2100.

We would like to thank:

You will be given 5 problems, one of which is divided into two subtasks, and you will have 2 hours to solve them.

One of the problems will be interactive, so please read the guide for interactive problems if you are not familiar with it.

The score distribution is 500 — 750 — 1250 — 2000 — (1500 — 1500)

UPD: Tutorial

UPD2: Congratulations to the winners!

Div. 2:

  1. AMDAM
  2. Aoi_Minoa
  3. bkdn23.baojiaopisu
  4. Valaki2
  5. JCY_

Div. 1:

  1. neal
  2. maspy
  3. A_G
  4. AmazingTalker_Frank
  5. heno239

We are thrilled to share some exciting news with you! We are teaming up with our partner, Constructor Institute in Schaffhausen, Switzerland, to bring you an amazing opportunity: a round supported and organized in collaboration with Constructor Institute, where you can explore Master's programs in Switzerland. Now we pass the floor to our partner.


Hello, Codeforces community!

Constructor Institute in Schaffhausen (Switzerland) is pleased and proud to have the opportunity to support the round on Codeforces. We invite you to participate in it!

If you are passionate about studying in Switzerland and pursuing a Master’s degree, we encourage you to fill out the form to initiate the application process and scholarship interview. Our Institute representatives will be in touch with you to guide you through the next steps.

We offer two Master programs, both taught in English, with flexible duration of 1.5 or 2 years full-time:

Our Master's programs open doors to a world of opportunities. Many of our students have secured high-profile roles in multinational companies in Switzerland and across the globe. Additionally, our programs also serve as an excellent preparation for Ph.D. research in fields such as software engineering, cybersecurity, artificial intelligence, and other advanced topics.

​​We understand that financing your education can be a concern, and to support your journey, we are offering the following scholarships:

  • Tuition waiver scholarships — 20,000 CHF per year, covering the cost of tuition fees.
  • Full scholarships — 20,000 CHF per year, covering the cost of tuition fees, along with a monthly stipend of 2,000 CHF to assist with living expenses in Schaffhausen.

Both scholarships are non-repayable, providing you with financial peace of mind.

To learn more about Constructor Institute and its programs, visit our webpage.

Eligibility for the programs and its available scholarships:

  • You have obtained or you will obtain a Bachelor’s degree in Computer Science, Software Engineering, Physics, or a related field before the program starts.

To express your interest in this opportunity, please complete the form:

Complete the Form

We wish you good luck in the competition and enjoy solving the problems.

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