The 1st Universal Cup. Stage 7: Zaporizhzhia Hello everyone! The 7th Stage of the 1st Universal Cup: Zaporizhzhia, will be held on March 11th, 2023. The contest is based on the Day 2: Oleksandr Kulkov Contest 3 from the [Osijek Competitive Programming Camp 2023](https://codeforces.me/blog/entry/113438). Please, don't participate if you have seen these problems. Authors of the problems: [user:adamant,2023-03-07], [user:fedimser,2023-03-07], I would also like to thank [user:-is-this-fft-,2023-03-07] for the help with the preparation of the contest. We hope you will like the problems! You can participate in the contest in the following three time windows: * Mar 11th 13:00 — 18:00 (UTC +8) * Mar 11th 19:00 — 24:00 (UTC +8) * Mar 12th 02:00 — 07:00 (UTC +8) Please note that you can see two scoreboards in DOMjudge. The 'Local Scoreboard' shows the standings ONLY IN THE CURRENT TIME WINDOW. And the 'Combined Scoreboard' shows all participants, including the onsite participants, and the cup partici...

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Crypto Cup 1.0 Hello everyone. [Soon](http://www.timeanddate.com/worldclock/fixedtime.html?msg=Crypto+cup+1.0&iso=20141101T15&p1=246&ah=6), On the night after the Halloween, there will be a Codeforces gym contest, named **Crypto cup 1.0**.  Like its name, it's a cryptography contest and for all problems, you are given some sample encryptions encrypted using a certain algorithm and you have to write a program to decrypt the given messages. There will be 18 problems and you have 6:30 hours to solve them. I hope it will be interesting. Problems are prepared by me ([user:PrinceOfPersia,2014-10-21]) and tested by [user:DamonSalvatore,2014-10-21] also thanks [user:Swift,2014-10-21] for editing problem statements. For practicing cryptography, we recommend [SecutiryOverRide](http://securityoverride.org)'s cryptography challenges. Also, this round needs a little Algorithm and CS knowledge.Don't forg...

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Spectral::Cup 2026 Round 3 (Codeforces Round 1110, Div. 1 + Div. 2) Hello Codeforces! I am glad to invite you to participate in [contest:2245], which will start on [contest_time:2245]. You will be given **2 hours and 30 minutes** to solve **8** problems, where **one problem** will be split into subtasks. Also, there is **at least one** interactive problem, so you are recommended to read the [guide](https://codeforces.me/blog/entry/45307) to interactive problems if you have not encountered them before. Note that **hacks will be disabled** for problems A to D. All problems are authored and prepared by myself. Note the [rule restricting the use of AI](https://codeforces.me/blog/entry/133941). If you are caught breaking this rule, you will be thrown into [user:SSerxhs,2026-07-09]'s basement. For your own well-being, I suggest adhering to the rules. I would like to thank the following people for helping make this round possible! - [user:SSerxhs,2026-07-09] for his/her satisfactory coordination. - [user:Alexdat2000,2026-07-12] for trans...

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The 2nd Universal Cup. Stage 13: Shenyang Hello! I'm happy to announce The 2nd Universal Cup. Stage 13: Shenyang, which will be held on December 9th, 2023. This contest is an official ICPC Regional Contest — The 2023 ICPC Asia Shenyang Regional Contest. It is the 9th consecutive year that Northeastern University has hosted the ICPC Asia Shenyang Regional Contest. Great thanks to the host school for preparing the Regional, and the hard work done by all staff and volunteers for this contest. <img src="/predownloaded/24/83/2483ceaf571339751e32ed2e5401c5d08bd6db18.jpg" width="35%" height="35%" /> <img src="/predownloaded/e3/fb/e3fb46fa993b6b46dadb89ee7b0aac495abb5d29.jpg" width="27%" height="27%" /> <img src="/predownloaded/00/8c/008c2d13555c6d9b32427762cc02559356f52e08.jpg" width="35%" height="35%" /> The authors for preparing the contests: [user:Sulfox,2023-12-06], [user:quailty,2023-12-06], [user:lzr_010506,2023-12-06], [user:calabash_boy,2023-12-06], [user:Gromah,2023-12-06]. The testers for their valuable advice: ...

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ICO 2025 Teams ###### _ICO stands for the International Cybersecurity Olympiad and has little to no connection to competitive programming. This blog aims to introduce participants. Many of them happen to be competitive programmers. It also focuses on raising awareness and promoting cybersecurity as a recognized field, much like CP. For more details, visit the [official ICO 2025 website](https://ico2025.sg/)_ ##### I've created a Discord server for ICO participants and cybersecurity specialists where you can join from [here](https://discord.gg/Gbn9TuANzh)! A few days ago, the selection process for the ICO 2025 Azerbaijan Team was completed. You can view the [Prelims Contest Standings here](https://docs.google.com/spreadsheets/d/1wZJiSppZYO7lIOcQFgva9ZTT9mwgu6xeumwsBPatWPM/edit?usp=sharing). Since six participants tied for second place, an additional offline contest was held to finalize the team. Here is the official ICO 2025 team of Azerbaijan: - Aliyyiakbar Shirinli ([user:AkbarKING,2025-...

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[Rated, Prizes!] DYTECHLAB Cup 2022 Round Announcement [Div.1 + Div.2] <img src="/predownloaded/ff/85/ff85322f740c69d9497bd061c096bad892766f13.png" align="right" style="height: 400px;" alt="text"/> > Hello Codeforces. Hoping you're having a wonderful day! ^_^ # DYTECHLAB Cup 2022 This October, we invite you to the **first ever [contest:1737]** that will start on [contest_time:1737]. The problems were prepared by members of our company who _share a passion for Competitive Programming_. It is an open and rated round for both divisions. The round will consist of **7 problems** and will be **150 minutes** long. We wish everyone good luck and have a positive delta! ### Prizes - 1st place: **US$200** cash prize - 2nd place: **US$100** cash prize - 3rd place: **US$50** cash prize Also, we understand that contestants like dope **MERCHANDISE**, so we are giving away lots of them! - **Top 20** will get a merchandise package which will include: a t-shirt **with your Codeforces handle on it**, a notebook, 2 pens, and a sports bag. - **3...

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Meta Hacker Cup Finals 2025 The [2025 Meta Hacker Cup Finals](https://www.facebook.com/codingcompetitions/hacker-cup/2025/final-round) will be happening this Saturday, starting at [6:00 AM Pacific](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Meta+Hacker+Cup+Finals+2025&iso=20251220T06&p1=224&ah=4). **The round is concluded! [Final standings](https://www.facebook.com/codingcompetitions/hacker-cup/2025/final-round/scoreboard)** Congratulations to [user:tourist,2025-12-20] for becoming six-time champion of Meta Hacker Cup! Scoreboard reveal video is [here](https://www.facebook.com/hackercup/live_videos)!  We'll reveal the scoreboard and winner on a [facebook livestream](https://www.facebook.com/hackercup/live_videos) roughly in 30 minutes after the contest ends. Here is the list of 2025 Meta Hacker Cup finalists: | Contestant | CF handle | 1st | 2nd | 3rd | | ----------- | ----------- ...

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i will become specialist and beat chenlinxuan0226 balllightning37 → Bug in rating graph? New comment(s) ETO_leader → Could Codeforces add official AI translation for Codeforces Rounds? New comment(s) Proof_by_QED → Codeforces Round 1003 (Div. 4) Editorial New comment(s) negative-xp → Let's stop making anti-GPT problems? Text created or updated rahulgandhi1970 → sleepyAdarsh might be cheating! New comment(s) sevlll777 → Codeforces Round 1004 (Div. 1, Div. 2) Text created or updated sevlll777 → Codeforces Round 1004 (Div. 1, Div. 2) Editorial New comment(s) Timosh → Div. 1 as a CM New comment(s) Hussien_Ibrahiem → Group Status not show submissions New comment(s) Necropost Guslix → I have 2 accounts in CF 1004 standings New comment(s) innocentkitten → Codeforces Round 996 (Div. 2) New comment(s) AlgoMaster2024 → 14 Year Old Seeking a USACO Tutor to Reach Platinum Text created or updated New_and_simple → Brute force solution for CF 1004 C Text created or updated bacxiuda → How to access "points" fiel...

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Teens Ramadan Marathon 2025. ## Hi, CF community :) I'm pleased to announce and invite you to the 1st edition of [Teens Ramadan Marathon](https://codeforces.me/group/H3jEt2ZcBo), a Marathon managed by [Obour STEM CS Club](https://obourcsclub.org/) and [Gharbia STEM Hack Club](https://hack-club-gh.github.io/Gharbia-Branch/index.html), designed by some Egyptian teens (and 2 university students) that will run throughout Ramadan month, from 1st Ramadan to 29th Ramadan (corresponding to 1st March to 29th March in Gregorian calendar). The Marathon will start in [Saturday, 1st of March, at 10PM (UTC+2)](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Teens+Ramadan+Marathon&iso=20250301T22&p1=53), and will end in [Saturday, 29th of March, at 10PM (UTC+2)](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Teens+Ramadan+Marathon&iso=20250329T22&p1=53). It will consist of four separated contests, each contest will run for 7 days and one problem will be added daily to the running contest at 10 PM (a...

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Who is SH00QiNan and how do you think? On yesterday's [ABC363](https://atcoder.jp/contests/abc363/standings), [SH00QiNan](https://atcoder.jp/users/SH00QiNan) got the first place in a very-very short time. It's a new account and never competed before. Also, there's a CF account named [user:SH00QiNan,2024-07-21], which is also a completely new account.  Some of the gossips I heard as this account is controlled by six China NOI Silver player. (I don't believe) But even six best player can't solve problem so fast, I think.  It's Affiliation is QFLS. I'm not sure what QFLS is, but I am in Changsha, Hunan, China, and there is a school named Qingzhuhu Foreign Language School, but it's a nine-year-school (which means the students are 6~15 yo)  What do you know about this account, and what do you think?  Purr, our Tourist and JiangLY! The 1st place is stolen by this account!

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ATMOS CodeDash '19 Results Hello again! **ATMOS CodeDash '19** has ended and here are the winners: **1st Prize &mdash; [user:_shanky,2019-10-13]** (CodeChef Handle: **bhavy_jain**) ((IIT BHU &mdash; Varanasi) **2nd Prize &mdash; [user:Jeel_Vaishnav,2019-10-13]** (CodeChef Handle: **jeel_vaishnav**) (Nirma University) **3rd Prize &mdash; [user:cerberus97,2019-10-13]** (CodeChef Handle: **c1_6**) (IIIT Delhi) Full standings can be seen [here](https://www.codechef.com/rankings/ACD2019) Congratulations to all the winners! We will reach out to you via mail. I hope everyone enjoyed the problemset! We would love feedback on the problemset to improve the event next year. So feel free to comment below. See you next year! **EDIT** Thanks to **[user:cerberus97,2019-10-14]** , we found a minor bug in the test cases of the problem CHTIME. To fix this, we removed all cases which had created a discrepancy and manually rejudged all submissions to the problem. In addition to t...

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EJOI 2017 Day 1 online mirror Hello, Codeforces! The 1st [European Junior Olympiad in Informatics](http://ejoi.org/) takes place in Sofia, Bulgaria, from September 07 (arrival day) to September 13 (departure day) 2017. EJOI is a significant event, a stepping-stone, in the development of the elite of the IT industry in Council of Europe member states. CS Academy will host the online mirrors of both competition days. The [first contest](https://csacademy.com/contest/ejoi-2017-day-1/) starts on [Saturday, September 09, 11:00:00 UTC](https://www.timeanddate.com/worldclock/fixedtime.html?msg=EJOI+2017+Day+1&iso=20170909T11&p1=1440&ah=4), one hour after the onsite competition ends. The round will be **unrated** on CS Academy. #### Contest format - You will have to solve **3** tasks in **4** hours. - There will be full feedback throughout the entire contest. - The tasks will have partial scoring. The maximum score for each problem will be 100 points. - There will be no tie breaker, so two users having the s...

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EJOI 2017 Day 2 online mirror Hello, Codeforces! The 1st [European Junior Olympiad in Informatics](http://ejoi.org/) is taking place in Sofia, Bulgaria, from September 07 (arrival day) to September 13 (departure day) 2017. CS Academy will host the online mirrors of both competition days. The [second contest](https://csacademy.com/contest/ejoi-2017-day-2/) starts on [Monday, September 11, 11:00:00 UTC](https://www.timeanddate.com/worldclock/fixedtime.html?msg=EJOI+2017+Day+2+Online+Mirror&iso=20170911T11&p1=1440&ah=4), one hour after the onsite competition ends. The round will be **unrated** on CS Academy. #### Contest format - You will have to solve **3** tasks in **4** hours. - There will be full feedback throughout the entire contest. - The tasks will have partial scoring. The maximum score for each problem will be 100 points. - There will be no tie breaker, so two users having the same total score at the end of the contest will share the same place in the standings. If you find any bugs please ...

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COderfocers Codeforces | In English По-русски pathetique | Logout HOMETOPCATALOGCONTESTSGYMPROBLEMSETGROUPSRATINGEDUAPICALENDARHELP → Pay attention Before contest Codeforces Global Round 26 3 days Register now » *has extra registration → pathetique pathetique User''s contest rating in Codeforces communityRating: 1448 User''s contribution into Codeforces communityContribution: -77 Settings Blog Favourites Teams Submissions Problemsetting Groups Talks Contests → Top rated # User Rating 1 tourist 3757 2 jiangly 3647 3 Benq 3581 4 orzdevinwang 3570 5 Geothermal 3569 5 cnnfls_csy 3569 7 Radewoosh 3509 8 ecnerwala 3486 9 jqdai0815 3474 10 gyh20 3447 Countries | Cities | Organizations View all → → Top contributors # User Contrib. 1 maomao90 171 2 awoo 164 3 adamant 163 4 TheScrasse 159 5 maroonrk 155 6 nor 154 7 -is-this-fft- 152 8 Petr 147 9 orz 145 10 pajenegod 144 View all → → Favourite groups # Name 1 X-Camp 402H 2022 Fall View all → → Fi...

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PSUT JCPC Qualification 2026 Tutorial Hints are mostly related, so you have to think and get some observations before understanding the next, make sure to understand the code before you submit it as well, "Most problems in life are due two reasons: act without thinking, think without acting" ~the,2026-08-02 poet,2026-08-01 Big thank you to the testers for improving this problem set beyond what it was, [user:the_seal,2026-08-02] , [user:Rayo,2026-08-02], [user:samsoom,2026-08-02], [user:lazlooz,2026-08-02] The contest exist in the group so make sure to join https://codeforces.me/group/ppRciMeJFg Some of these problems were inspired from other problems across the internet, "If I have seen further, it is by standing on the shoulders of giants." ~the,2026-08-02 poet [Problem A: MrMoon creates Lucky Number Seven Command](https://codeforces.me/group/ppRciMeJFg/contest/707652/problem/A) ================== ### 7 [Problem B: Moon creates seal backflips](https://codeforces.me/group/ppRciMeJFg/contest/707652/probl...

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