About the Universal Cup, the Semifinals, and myself... Hey'all! This gonna be a long post, so let me put an important TLDR here first: we are going to host **The 3rd Universal Cup Semifinals**, which will take place on August 24, 2025 **online**, at [11:00 (UTC)](https://www.timeanddate.com/worldclock/fixedtime.html?msg=The+3rd+Universal+Cup+Semifinals&iso=20250824T19&p1=33&ah=5). This contest will be a part of our Finals Team Selection, which the detailed rules and announcements will be published later next week. --- Now for some extra context, if you're interested. Last week, we hosted the [last online stage](https://mirror.codeforces.com/blog/entry/143954) of The 3rd Universal Cup. After that, I posted a [feedback form](https://docs.google.com/forms/d/1g5Txhiirh_lRsvGfkYWRozu0WDDGK31IAXjB7VgeVoM/edit) on our discord server. I received lots of thoughtful responses (P.S — it's still open, so feel free to fill it out if you haven't yet!). I've read through all the feedback, and I'd like to share a few thoughts. ### On the Number...

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WF23 Luxor _(Long blog ahead. Reader discretion advised.)_ I feel we have a rather interesting WF story (note: we did the 47th finals, as the University of Maryland, <b><i>as 2 people</i></b>... explained below), so I figured I'd tell it. Exposition ---------- It actually starts way before WF, too. Our teams were decided on (some form of) merit based on an internal qualifier. My team for the regional and NAC (North America superregional) ended up as {me, [user:Navick,2024-04-24], [user:mr.banana,2024-04-24]}. We did [fairly](https://nasouth22d1.kattis.com/contests/nasouth22d1/standings) [well](https://nac.icpc.global/wp-content/uploads/2023/06/NAC23-scoreboard.pdf) in those. However, for WF, my two teammates only had single-entry visas for the US, meaning that if they left, they couldn't come back into our country. So they couldn't really go with me... Luckily, in such situations, ICPC lets you just replace your teammates. So we held another internal qualifier, and ended up with two ...

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ICPC 2021 North America Championship Made Virtual Last Minute North American ICPC participants were all ready to go to Orlando, Florida for a week-long event including NAPC (North America Programming Camp) and NAC (North America Championship), which will decide the 2021 World Finalists from North America. With less than a week's notice, and after all travel plans were arranged by the teams, the following announcement was made. > Dear NAC &mdash; NAPC Participant, > Due to the surge in COVID-19 cases across the country and, in particular, the region surrounding the event location, the 2021 North America Programming Camp (NAPC) and North America Championship (NAC) events will be conducted virtually. Registration fees paid by NAPC teams will be refunded. The health of our participants, university partners, and all of our communities is always our top priority. > Though conducted virtually, the NAPC-NAC will take place in the same timeframe (8-15 Aug.) with largely the same schedule as originally scheduled. We will finalize these details in ...

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Comments on World Finals Baku's Problemset Distribution **UPD:** I modify the title to a more moderate version. I once again would like to emphasize that I am only questioning the medal distribution should be better and many things can be done to prevent a close cut-off line this year. I am sorry for whoever feel offended. Let’s keep this as a discussion and exchanging of views. Now that the results are released, let's congratulate all teams that made it to the World Finals, and especially those who have won medals and the trophy. **Disclaimer 1:** I respect all efforts from judges, and this blog is purely based on my observations and is not intended to be personal. It is not easy to make a problemset and your work is greatly appreciated. **Disclaimer 2:** I haven't read the problemset, which means I know nothing about the problems so far. Therefore, feel free to consider this as nonsense. **Disclaimer 3:** I don't know anything about the pipeline in the World Finals' problem setting. OK, I only want to emphasize one phenomen...

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The ICPC NAC 2026 Experience Preamble ------------------ I thought writing a short blog about my experience at the NAC would be interesting, so here we are. This year's NAC was held in UCF from March 18-23. This is the third time in a row that the NAC is hosted in UCF. I will put all comments regarding the problems in spoiler tags, since this contest may or may not be used in a future universal cup. Since this is my third year at the NAC hosted at the exact same place, there is a sense of familiarity with how things are run. For example, the food, hotels, and contest location hasn't changed much in the last couple of years. Arrival Day ------------------ The flight to Orlando was very eventful for our team. We had a tight connection at Toronto and our initial flight was significantly delayed. It was so bad to the point that during the flight all of us received emails that we got rebooked to different flights. Despite this, we tried our best to make the flight to Orlando. We ran across the airport to catc...

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ICPC North America Championship: Call for Fun Facts Fun Facts about NAC Teams ================== Are you or someone you know attending the North America Programming Camp? If so, we'd love to get some fun facts about the teams that are here! Please submit your fun facts [in this google form](https://forms.gle/6urswk25LchFw2uR6), or send them in a direct message to me, [user:SecondThread,2023-05-27] on Codeforces!  What kind of facts are you looking for? ------------------ We're looking for anything exciting, interesting, or varied about your team that you're willing to share. Some great examples that we've seen in the past include: - I play Smash Melee competitively in my free time - One of our team members (his_handle) is getting married within a week of finals - I'm surprisingly not actually a Computer Science major, instead I'm majoring in x and plan to use it for y. - 2/3 of our team uses the non-C++ programming langua...

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Osijek Competitive Programming Camp 2023 winter Hi everyone! <center><a href="https://ocpc.mathos.unios.hr/index.php"><img src="https://ocpc.mathos.unios.hr/images/ocpc.svg" height="100px"></a></center> I am happy to announce the [Osijek Competitive Programming Camp](https://ocpc.mathos.unios.hr) that is scheduled to happen on **18-26 February 2023** in Osijek, Croatia. The camp is hosted by the [Department of Mathematics at J. J. Strossmayer University of Osijek](https://www.mathos.unios.hr/index.php/en/) and is brought to you by the organizing team of [user:adamant,2022-12-21] (that's me!), [user:-is-this-fft-,2023-01-06], [user:mblazev,2023-01-06], [user:Tomx,2023-01-06] and [user:antontrygubO_o,2023-01-05]. The camp is inspired by various competitive programming camps that we attended during our active years in ICPC, and is aimed to help college students prepare for ICPC regional contests and finals. The camp will consist of 7 ICPC-style contests and 2 days off. Up until now, most top competitive programming training...

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NAC Vlogs | Final Day, Disney World, Qualified to the WF, Won Bronze and South ### First day We have North America Championship from today (May 23rd) to May 28th in Orlando, Florida. This competition is for choosing the teams qualifying to ICPC WF 2024 in Kazakhstan. I will make a vlog for each day. I'm trying to make each one of these vlogs 15 mins. My first try wasn't very successful and the first video is about half an hour. (It was good and I couldn't trim more than this) By the way, we did the real duel with [user:galen_colin,2024-05-24] and we tried to headshot each other using frisbees. We are both alive but injured. Everyday, This post will be updated by the vlog of that day. Hope you'll enjoy, feel free to give me suggestions about the next ones. And definitely wish UMD White luck :) ### Second Day I heard a sad news from Mohamed [user:Bakry,2024-05-25] today. As he said, Iran and Israel cannot attend IOI 2024 onsite and this is told to them about a year ago. I personally don't know what can we do in this situation to prevent such thin...

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Teams Going to the 2020 ICPC North American Championships Now that the first North American ICPC regionals are complete, I'm starting a list of teams attending the North American Championships next February. To start things off, the list will include team names and ranks. However, please comment below if you know any of the members of the advancing teams--I'll fill in their Codeforces handles if they have them or their names if not. (To avoid leaking sensitive personal information, please do not provide someone's Codeforces handle if their profile does not include their real name and you haven't received permission from them to post their username.) Additionally, if you notice any errors, let me know. In particular, I'm gathering a list of schools by taking the top teams at each regional, but I may need to adjust this list if any teams choose not to accept their NAC invitations. --- #East Central | Rank | University | Team Name | Member 1 | Member 2 | Member 3 | | ----- | ------- | ------ | ---------- | -------- | -----...

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Partial Scores in ICPC Contests The ICPC CLI Symposium during World Finals 2025 and the presentation during the NAC 2026 suggested the idea of bringing partial scoring problems to ICPC contests. Based on my understanding, the NAC judge team is announced to have a medium-level task with subtasks/partial scores included in NAQ 2026 / NAC 2027. <div class="row"> <img src="https://qoj.ac/files/Qingyu/scoring.jpg" style="height: 262.0px;max-width: 100.0%;max-height: 100.0%;"> <img src="https://qoj.ac/files/Qingyu/scoring2.jpg" style="height: 262.0px;max-width: 100.0%;max-height: 100.0%;"> </div> As a judge/chief judge for several Asia EC regionals over the past few years, I've been eager to introduce more innovative ideas in regional contests. However, I feel the idea may lead to some non-trivial changes regarding problem-setting and competition strategy. Over the past few days, we, along with many other judges, coaches, and contestants, had several discussions about this proposal. Since I have yet to see...

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Teams Going to the 2026 ICPC North America Championship All regionals for the 2026 NAC have been completed. AFAIK there's been no word from ICPC on exact qualifications, but I've made some educated guesses. Will update when official info is released. Please comment the codeforces handles of your university's team if you know them, and I'll add them to the list. :) --- # **WEST** ## **[Rocky Mountain](https://rmc25.kattis.com/contests/rmc25/standings)** | University | Member 1 | Member 2 | Member 3 | | ------------------------ | -------- | -------- | -------- | | University of Alberta | [user:asiad,2025-11-29] | [user:digital_vest,2025-11-29] | [user:jxu,2025-11-29] | | Arizona State University | [user:BenjaminJ,2025-12-04] | [user:sahajrastogi,2025-12-04] | [user:tgossett,2025-12-04] | | Colorado School of Mines | [user:WhimsicalCode,2025-12-01] | [user:Dell_Know,2025-12-01] | [user:Leviathan102,2025-12-01] | | University of Calgary...

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pol2dom: Convert problems from Polygon to DOMjudge TL;DR: I am advertising [pol2dom](https://github.com/dario2994/pol2dom): a tool to convert a set of problems prepared in Polygon into a DOMjudge contest. The whole process is automated: downloading the Polygon package, converting it into a DOMjudge package, and uploading the DOMjudge package to a DOMjudge server. If you are organizing a contest that uses DOMjudge, I invite you to give `pol2dom` a try. #### Long story [Polygon](https://polygon.codeforces.com/) is the platform used to prepare problems for Codeforces rounds (and, at least one year ago, for Codechef rounds). It has [many issues](https://mirror.codeforces.com/blog/entry/90914) but, as far as I know, it is the best platform for preparing competitive programming problems. It has a large number of checks that catch common mistakes, it is hosted online, it allows a coordinator to quickly review the preparation, and so on. As everyone, I would like to see Polygon improve (for example, with a decent UI), but there's nothing ...

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2024 ICPC North America South Regional On November 16th starting at [1:30 PM US Eastern Time](https://www.timeanddate.com/worldclock/fixedtime.html?msg=2024+ICPC+North+America+South+Regional&iso=20241116T1330&p1=867&ah=5), the 2024 ICPC North America South Regional will take place. This year, [user:galen_colin,2024-11-16] and I will host the official contest broadcast, starting shortly before the beginning of the contest, on the [ICPC Live YouTube channel](https://www.youtube.com/watch?v=pd2HVL-GlnQ). During the stream, we'll * Follow the scoreboard and discuss the contest * Discuss the problems and possibly solve a few of them (though unlike some of my past personal ICPC streams, solving problems and competing for the highest score will not be the main goal of the stream) * Talk about the teams competing to advance to the 2025 ICPC North America Championship * In keeping with recent tradition, I'm hoping to share some fun facts about the competing teams. If you're the contestant or coach of a competing team and ...

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Returning to In-Person GCJ/Hacker Cup Finals In the past, most elite programming competitions (e.g. IOI, ICPC, TopCoder Open, AtCoder World Tour, GCJ, Hacker Cup) have held their final stages in person. In 2020 and 2021, however, most of these contests were moved online. This was unfortunate, but understandable given the circumstances: in 2020, the state of the pandemic clearly did not allow for extensive travel, and while the dangers decreased by late 2021 as a result of rising vaccination rates around the world, there was still sufficient uncertainty to justify holding events online in 2021. This year, however, both Google Code Jam and Meta Hacker Cup have committed to hosting online finals. [**UPD:** Meta has retracted its commitment to a virtual finals, so it seems that the plans for MHC are still up in the air.] I believe that this is a highly unnecessary precaution--there is plenty of evidence showing that it is possible to successfully run an in-person event in 2022. Notably, TopCoder has committed to hosting the...

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OCPC 2026 Winter Hi everyone! <center><a href="https://ocpc.camp"><img src="https://ocpc.camp/images/ocpc_light.svg" height="80px"></a> <a href="https://icpc.foundation/"><img src="/predownloaded/43/08/43086529a28ccb5c9f2f2eec560ffa85e09c6881.svg" height="80px"></a></center> <center> <b>Supported by</b><br> <a href="https://www.janestreet.com/join-jane-street/open-roles/?type=students-and-new-grads&location=london"> <img src="/predownloaded/ee/f2/eef26616a3661c658d1545f18ed21fabb14d5871.svg" height="40px" style="margin: 10px 10px 10px 10px;"></a> <a href="https://www.hudsonrivertrading.com/"> <img src="https://ocpc.camp/images/HRT.svg" height="40px" style="margin: 10px 10px 10px 10px;"></a> <a href="https://www.silares.com/"> <img src="https://ocpc.camp/images/silares-red.svg" height="40px" style="margin: 10px 10px 10px 10px;"></a> <a href="https://pinely.com/"> <img src="/predownloaded/0a/0f/0a0f3f67435d1f6e467bc7203d4a2090ba8f92cc.svg" height="40px" style="margin: 10px 10px 10px 10px...

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2025 ICPC North American Championship Stream ICPC North American Championship ================== Good morning! Tomorrow, [May 26th at 10:00 AM EST](https://www.timeanddate.com/countdown/generic?iso=20250526T10&p0=867&msg=ICPC+North+American+Championship&font=sanserif), the 2025 ICPC North American Championship will begin. The best teams from the United States and Canada will compete to become the next ICPC North American Champion and see which teams will qualify for a spot at the upcoming ICPC World Finals in Baku Azerbaijan!  The contest will be 5 hours, and will happen in person in the beautiful Orlando, Florida, at our host university, the University of Central Florida. During the contest, we’ll host a [livestream](https://youtube.com/icpclive) with fun facts, coaches, judges, and others. - Watch the contest broadcast live & support your team [https://youtube.com/icpclive](https://youtube.com/icpclive) - Follow the live scoreboard [https://nac.icpc...

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Teams Going to the 2022 ICPC North America Championship The teams advancing to the NAC this year were announced today. In previous years, someone has made a post with the list of qualifying teams and their known codeforces handles. This year that person is me. If you have any of the missing data, please let me know and I'll add it to the tables. East Central North America ================== | University | Team Name | Member 1 | Member 2 | Member 3 | |-------------------------------------|---------------|------------|----------|----------| | Carnegie Mellon University | CMU1 | ~conqueror_of_tourist,2022-03-26 | ~xumingkuan,2022-03-26 | ~summitwei,2022-03-26 | | University of Waterloo | Waterloo Gold | ~pwypeanut,2022-03-25 | ~ChrisT,2022-03-25 | ~mariand,2022-03-25 | | University of Michigan at Ann Arbor | Victors | | | | | Purdue University | Purdue UWU | | | ...

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The 2026 ICPC North America Championship Hello Codeforces! We are glad to invite you to follow the 2026 ICPC North America Championship! The live broadcast will be on the ICPC Live YouTube channel starting at 10am EDT! <center style="margin: 2em;"> <iframe width="560" height="315" src="https://www.youtube.com/embed/g4My7gavMOc" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe> </center> Some other links for more NAC content! - [Photo gallery](https://news.icpc.global/galleryNAC/?album=2026) - [NAC Scoreboard](https://nac.icpc.global/scoreboard/2026) - [NAC Problemset](https://nac.icpc.global/problems/2026) - [NAC Online Judge](https://onlinejudge.nac.icpc.global/public) &mdash; register [here](https://icpc.global/regionals/finder/NAC-Online-2026)! - [NAC Facebook](https://www.facebook.com/na.icpc.io/) If you have any fun facts about NAC teams, please submit them [here](https://d...

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Teams Going to the 2023 ICPC North America Championship Most North America ICPC regionals have been held. While we don't yet know who is going to NAC, it's reasonable to guess that the slot distribution will be similar to last year. So here is a list of teams who qualified for NAC assuming the same distribution. Note that all regions are guaranteed at least 3 slots, and I would be relatively surprised if any region received less than 4. Update: It looks like an official list has been [posted here](https://icpc.global/regionals/finder/North-America-Championship-2022/teams). I've updated the tables below in accordance, with the exception of Pacific Northwest, which has some irregularities. Update 2: UC Davis now appears on the list, so everything seems normal now. 48 total teams invited. Update 3: Stony Brook University and Northeastern University have been added to the list, for a total of 50 teams. I expect there will be no more additions beyond this. If you know the codeforces handles of any team that is not yet filled in, ple...

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North American Championship 2020! New Rules Updated on Oct. 15th **OK the rules are changing again (on Oct. 15th):** **Eighteen (18) of the 2019 ICPC North America teams will advance to the 2020 ICPC World Finals by meeting at least one of the following criteria:** **(1) Win the 2020 ICPC North America Championship, (2) Win one of six medals at the 2020 ICPC North America Championship, (3) Win a wildcard slot at the 2020 ICPC North America Championship, or (4) Win one of the eleven 2019 North America Regional Contests.** (Sorry I am also a bit confused here. (1) is definitely included in (2), and I have no idea about what a wildcard slot is. Does anyone have any idea?) ### Intro Disclaimer: I am not an official ICPC staff. I write this post just to summarize the information about the North American Championship next year and earn some contribution (sssshhhhhh...!). Last evening, the information about the North American Championship (NAC for short) is released by the ICPC official. Finally, the schools in North America can have an ...

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Stanford Local Programming Contest 2026 **Edit: Registration deadline extended by 12 hours -- to 9PM pacific time today!** Hello Codeforces! We ([user:ritwin,2026-03-26], [user:nikilrselvam,2026-03-26], [user:spycoderyt,2026-03-26], [user:lethan3,2026-03-26], [user:Mokuroh54,2026-03-26], [user:andy0liang,2026-03-26], [user:applepi216,2026-03-26], [user:bitset,2026-03-26], [user:minifinity,2026-03-26]) are excited to announce the **Stanford Local Programming Contest (SLPC 2026)** — a 3-hour ICPC-style team contest with **over $3,000 in prizes**! SLPC has historically been Stanford's internal contest and ICPC team tryout. This year, we're opening it up to the broader competitive programming community. - **Date:** Saturday, April 4, 2026 - **Local Division:** In-person at Gates 403, Stanford students only -- lunch and boba provided! - **Open Division:** Online, open to everyone - **Registration deadline:** April 2, 2026 at 8:59 PM PDT ## Links - [Website](https://cs.stanford.edu/group/acm/slpc/) - [Regist...

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Teams Going to 2021 ICPC North America Championship Now that the advancing teams have been posted on the [ICPC website](https://icpc.global/regionals/finder/North-America-Championship-2020), I've put the attending teams below. Here's a link to the [NAC website](https://www.cecs.ucf.edu/NAC-NAPC/) (which may be updated soon?). Comment below with the handles or names of the team members of the advancing teams. Please do not post anyone's name or handle without their permission, since student names are not publicly available from ICPC (AFAIK). Let me know if any of the information below needs to be fixed. #Central Division | University | Team Name | Member 1 | Member 2 | Member 3 | | ------- | ------ | ---------- | -------- | -------- | -------- | | University of Wisconsin &mdash; Madison | teamname or NP = D?(AdjP)*N(PP)* | [user:bvd,2021-05-17] | [user:AquaBlaze,2021-05-17] | [user:ziyuan949,2021-05-17] | | University of Illinois at Urbana-Champaign | UIUC B | [user:jasonx3,2021-05-17] | [user:imbr92,2021-05-17] | [user:e...

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OCPC 2025 Summer Hi everyone! <center><a href="https://ocpc.camp"><img src="https://ocpc.camp/images/ocpc_light.svg" height="100px"></a> <a href="https://icpc.foundation/"><img src="/predownloaded/43/08/43086529a28ccb5c9f2f2eec560ffa85e09c6881.svg" height="100px"></a></center> <center> <b>Supported by</b><br> <a href="https://www.janestreet.com/join-jane-street/open-roles/?type=students-and-new-grads&location=london"> <img src="/predownloaded/ee/f2/eef26616a3661c658d1545f18ed21fabb14d5871.svg" height="60px" style="margin: 10px 10px 10px 10px;"></a> <a href="https://pinely.com/"> <img src="/predownloaded/0a/0f/0a0f3f67435d1f6e467bc7203d4a2090ba8f92cc.svg" height="60px" style="margin: 10px 10px 10px 10px;"></a> </center> ... And a happy May day! We are very happy to announce that OCPC (formerly, the _Osijek Competitive Programming Camp_) is back this Summer, on **June 21-29, 2025**! While the dates are pretty tight, they appear to be the ones that are most suitable (among all the summ...

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ICPC Dhaka: Call for Fun Facts Fun Facts About World Finals Teams ================== Are you participating in ICPC World Finals in Dhaka this week? Is someone from your team competing in World Finals? Did your best friend's brother meet someone whose cousin competed in regionals against a team who qualified? If so, we'd love to get some fun facts about the world finals team from you! If you have any, please submit your fun facts [in this google form](https://forms.gle/VXfD95C4yDsoR2FPA), or send them in a private message to me, [user:SecondThread,2022-11-05], on Codeforces!  #### What kind of facts are you looking for? Well variety is what makes things exciting, so we don't want to limit it too much. But for some inspiration, some good ones we've seen in the past include: - I play Smash Melee competitively in my free time - One of our team members (his_handle) is getting married within a week of finals - I'm surprisingly n...

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shenanigans **UPD: We are doing this duel May 19th (today) 17:00 GMT.** Hi. NAC (ICPC's North America Championship) is in less than two weeks. We've done absolutely fucking nothing for it. So, what better way to get in shape than public humiliation? Our team &mdash; [user:Shayan,2024-05-15], [user:sam571128,2024-05-15], and me &mdash; will stream (on [user:Shayan,2024-05-15]'s [channel](https://www.youtube.com/@CPwithShayan)) a form of head-to-head duel against each other. For now, it will be on something like 1400's. If this turns out to be fun, we may do more of these streams, on harder problems (maybe up to 3000). It will tentatively start on [Thursday, 9 AM ET](https://www.timeanddate.com/countdown/justmarried?iso=20240516T09&p0=263&msg=blastoff&font=cursive) (you'll also see it on the stream sidebar sometime soon) and will run for however long it takes me to have a winning score. Tentatively, the format will be the simple idea of choosing a large set of problems and racing to finish ...

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Introducing cp-notes.com — a place for your interesting competitive programming problems! **Update in 2025:** I've mostly forgotten about this site, but recently something rather funny came up: I was looking for a way to get a relatively large number of free subdomains (name of the url not mattering at all), when I realized I was still paying for cp-notes.com. So I tried to login to the AWS account owning the domain (which I haven't done in years), but it prompted me to check the email associated with it for a verification code... Unfortunately, I had used my Columbia university email out of convenience, but that has been disabled! (which I suspect has something to do with me dropping out?) I actually can still update the website (not that I was planning to) since I have some keypair saved which allows programmatic access, but not being able to use the console is a huge pain. I could also contact AWS support, but I feel like that would take a while... Anyways, it is time for me to express some of my frustrations: Fuck Columbia University! In addition to disabling my emai...

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How important is ICPC coaching? First I wanted to say how appreciative I am of the competitive programming community. I started participating in competitive programming contests 17 months ago and I can say that competiting online and in-person has helped me both push myself past what I thought I could be and meet some great people who share similar passions. About a month ago my team just barely qualified past the ICPC NA East Division (which consisted of NENA, ECNA, and GNY). This regional was especially challenging due to the breadth of good teams that showed up from East Central universities. This is the second time that my team made it to the national round, so we have a bit of experience. Now that my team is on a collision course with NAC for a second time, I am doing a retrospective on what my team can do to improve its chances at qualifying for the world finals. There are several aspects that my team has already improved upon leading up to this regional (ex/ patching blindspots, having useful reference d...

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Contest specifications **UPD:** немного поправил примеры Некоторые из вас знают про [мой плагин](http://mirror.codeforces.com/blog/entry/5162) для Idea. Одной из его самых интересных/полезных частей является автоматическое создание конфигураций с запуском задачи на всех тестах для некоторых сайтов, а именно --- Codeforces, CodeChef, Timus, E-Olimp и RCC. Некоторые другие плагины предоставляют похожую функциональность для других сред разработки и языков программирования. На текущий момент это реализовано за счет скачивания веб-страниц и их парсинга. Данный подход имеет сразу несколько минусов: - Повышается нагрузка на сервер (особенно в пиковое время вроде начала контеста) - Изменение в структуре веб-страницы приводит к необходимости исправлять парсер и выпускать новую версию. Кроме того, некоторые сайты не имеют четкой структуры оформления примеров (например, CodeChef) --- приходится использовать эвристики. Некоторые соревнования --- SN*S, OpenCup --- используют pdf для задач, что делает невозможным (или, по ...

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1<<12 Sub Live Stream! TLDR: [Stream at this time](https://www.timeanddate.com/worldclock/fixedtime.html?day=8&month=8&year=2020&hour=12&min=30&sec=0)! See you there! Hi everyone! I very recently reached 1<<12 subscribers on Youtube! To celebrate, I'm going to be doing my first ever livestream! I'll be on Youtube only this time (maybe I'll do both youtube and twitch later if there's demand for it). The stream will include looking at and trying to solve Code Jam Finals problems, which will be going on at the same time. **In general, live-streaming participation in a contest is considered cheating and is very bad. Do not do this for any public contests!** To be careful not to leak solutions or anything: 1. I will significantly delay my start of the round. 2. I will spend the beginning of the contest (where my participation overlaps with the real thing) reading all problems instead of solving. 3. I will not explain solution ideas of any problems until the round is over. That way, this isn't any mo...

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My Experience at ICPC Dhaka World Finals 2022 Hello, Codeforces! I participated at the Dhaka World Finals last month, and decided to write a blog about it. It's been a while since I've written, so I also decided to talk about a few other things: Indian regionals, Moscow World Finals, NAC, etc. So read on to know how I qualified for 3 World Finals across 2 continents and 6 different teammates, how my teammates got COVID at Moscow (and I was about to participate solo), getting the best rank IIT Bombay has ever gotten with a man down, and absolute devastation at Dhaka. I try to give an insight into the non-programming aspects as far as possible, while also trying to highlight the things to take away from the programming parts. The blog can be found [here](https://thesestraythoughts.blogspot.com/2022/12/icpc-world-finals-dhaka-2022.html). Thanks to [user:aryanc403,2022-12-27] and [user:lucasxia01,2022-12-27] for testing the blog. Please let me know what you think! <spoiler summary="Self-plug"> If you're interested in fol...

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Vlog: Winning Three Regions at North America (USA) ICPC Hey guys, Yesterday, we won both the Mid-Atlantic region of North America ICPC and the whole South Division (including the Mid-Atlantic, South Central, and Southeast Regions). Our team consists of Colin Galen ([user:galen_colin,2024-02-25]), Sam Lee ([user:sam571128,2024-02-25]), and me ([user:Shayan,2024-02-25]). We are UMD White from the University of Maryland. I created a vlog for the whole day of the contest. I hope you enjoy it. https://www.youtube.com/watch?v=OMozjSNLS14 The next round is NAC (the whole USA and Canada will participate). It will be in around 2 months. If we perform well, we will qualify to the World Final.

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Check out this! Congratulations to U of I team Ippatsu: [user:conqueror_of_tourist,2025-05-27] [user:YuukiS,2025-05-27] [user:satoshi,2025-05-27] winning NAC! Also check out this if you missed the stream! [user:tourist,2025-05-27] vs [user:conqueror_of_tourist,2025-05-27] picture!  （Thanks to [user:twosquares,2025-05-27] for extremely fast screenshoting!)

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ICPC North American Championship 2024 — Call for Fun Facts Fun Facts about NAC Teams ================== Are you or someone you know attending the North America Programming Camp? If so, we'd love to get some fun facts about the teams that are here! Please submit your fun facts [in this google form](https://forms.gle/UqDr227B2cuzUhaeA), or send them in a direct message to me, [user:SecondThread,2024-05-26] on Codeforces!  What kind of facts are you looking for? ------------------ We're looking for anything exciting, interesting, or varied about your team that you're willing to share. [Here are some examples from last year](https://youtu.be/PvUrAIEvFe4). Good luck in the competition, and we'll see you on the scoreboard! [Submit your fun facts!](https://forms.gle/UqDr227B2cuzUhaeA)

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Codesprint Los Angeles 2024 | Vlog | 6th place in total, 1st amongst universities Well, since you like it even more than educational content, I'm starting to upload more of them. Yesterday, we had Codesprint LA, an online ICPC style contest. Our team (UMD White, [user:galen_colin,2024-05-19], [user:sam571128,2024-05-19], and I) participated in it. We ended up ranked 6th in total, and 1st amongst the universities who participated. (teams that are eligible for NAC) Who won the first place? Well, as usual, [user:tourist,2024-05-19] with his two teammates. We recorded some parts of it. The cam was on by itself and we were trying to solve problems. I uploaded it to youtube and you can watch it [here](https://youtu.be/2QVtP_-HibI).  **And, as announced, we are going to do the duel today!**

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[meme] Benq > tourist  (Original picture by North America Comms. More NAC photos on [flickr](https://www.flickr.com/photos/187051365@N06/))

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Rutgers Programming Contest **Hello Codeforces!!!** We (the Rutgers University Competitive Programming Club) are happy to invite you all to compete in the online mirror of our fall semester programming contest. It's a 5h ICPC style team contest on [Sunday, Nov 17th, 1pm EST] (https://www.timeanddate.com/worldclock/fixedtime.html?msg=Rutgers+Programming+Contest&iso=20241117T13&p1=5276&ah=5) with a difficulty level somewhere between regional level and NAC. The contest was authored by [user:jdurie,2024-11-16], [user:nickbelov,2024-11-16], [user:ScalarField,2024-11-16], [user:jim,2024-11-16] and [user:bobbilyking,2024-11-16] orz You may sign up [here](https://forms.gle/A3zNWGspXxhr6cRi9) !!!!!!!!!!!! 

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Lockout Groups I recently had the opportunity to participate in a Lockout tournament at the NAC (thanks to Geothermal for organizing it btw!), and, in addition to being a ton of fun, it seems like a great way to practice typing quickly and working under pressure. However, I have not heard of Lockout happening outside of large, infrequent tournaments and high-profile one-on-one matches. Does anyone know of any groups (Discord servers etc.) that do lockout tournaments or one-on-one matches more frequently? Thanks in advance!

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[North America Championship 2020] Probability of placing blocks over a line? There is a line of length $T$ ($1 \leq T \leq 10^8$), divided into $T$ consecutive empty slots of length 1. There are N blocks ($1 \leq N \leq 10^5$). The i-th block has length $x_i$ ($1 \leq x_i \leq 10^3$). The sum of all block lengths is not greater than $T$. The $N$ blocks have to be placed over the line. This is done sequentially and randomly, and there is a chance that the process may fail: for the i-th block, we choose one of the $T$ slots uniformly, and then we find the first empty slot from there to the right. If no empty slot is found, we fail. If we find an empty slot, then we check if we can place the block (we need at least $x_i$ consecutive empty slots starting from the empty slot we just found). If there is not enough space to place the block, we fail. Otherwise, we place the block, move on to the next and repeat. If we never fail and manage to place all the blocks, we succeed. What is the probability of succeeding? (link to original problem from NAC 2020: https://open.k...

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Problems that I authored so far Hi everyone! I have been inspired [by](https://mirror.codeforces.com/blog/entry/108940) [recent](https://mirror.codeforces.com/blog/entry/108595) [events](https://mirror.codeforces.com/blog/entry/113093) to write this blog post. This list is not comprehensive, but mostly because I do not keep detailed logs of problems I have written. There are a few things you will notice after reading through these problems. In no particular order: 1. Most of these problems are not "high-quality" &mdash; they would never see the light of day on a CF round for example. This is mostly due to my lack of skill in generating "high-quality" problems. You'll see that a lot of my problems are generated from observing real-life events and then constructing problems out of those scenarios. There are many ideas that have been proposed and thrown into the void because they were worse. I think there are a couple problems in this list that are actually good problems, but most of them I am not particularly proud of. 2. The diffic...

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