What if tourist goes rainboy mode? (Simulation) DISCLAIMER: NO TOURISTS AND RAINBOYS WERE PINGED Ah yes, two names that most people on Codeforces have heard -- <b>t<span style="color:red;">ourist</span></b> and <b><span style="color:purple;">rainboy</span></b>, one known as the CP Legend, and one as the user who does everything reverse. Such a great idea to put them together &mdash; a hypothetical user with the same ability as <b>t<span style="color:red;">ourist</span></b>, and solves problems the <b><span style="color:purple;">rainboy</span></b> way. _For those unaware of the "rainboy way", it means solving the problems in reverse order. In particular, if he cannot solve the final problem, he solves no problems in the contest._ Unfortunately, <b><span style="color:purple;">rainboy</span></b> had not yet reached red, peaking at 2398 rating. How far can this user go? We shall simulate this user through all the contests that tourist and rainboy took part in comparably, which adds up to 60 contests from [contest:745] to [cont...

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Educational Codeforces Round 51 [Rated for Div. 2] On [contest_time:1051] [contest:1051] will start. Series of Educational Rounds continue being held as [Harbour.Space University](https://harbour.space/) initiative! You can read the details about the cooperation between [Harbour.Space University](https://harbour.space/) and Codeforces in the <a href="http://codeforces.me/blog/entry/51208">blog post</a>. This round will be **rated for the participants with rating lower than 2100**. It will be held on extented ACM ICPC rules. The penalty for each incorrect submission until the submission with a full solution is 10 minutes. After the end of the contest you will have 12 hours to hack any solution you want. You will have access to copy any solution and test it locally. You will be given **7 problems** and **2 hours** to solve them. The problems were invented and prepared by Roman [user:Ajosteen,2018-09-19] Glazov, Ivan [user:BledDest,2018-09-19] Androsov and me. Good luck to all participants! Our friends at Harbour.Sp...

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Codeforces Round #274: editorial I am happy to present you author's ideas of solutions. Editorial of the first five problem is authored by &mdash; [user:HolkinPV,2014-10-18] and [user:gridnevvvit,2014-10-18], editorial for the last two problems is written by me. ### [problem:479A] In this task you have to consider several cases and choose the best one: ~~~~ int ans = a + b + c; ans = max(ans, (a + b) * c); ans = max(ans, a * (b + c)); ans = max(ans, a * b * c); cout << ans << endl; ~~~~ ### [problem:479B] The task is solved greedily. In each iteration, move the cube from the tallest tower to the shortest one. To do this, each time find the position of minimum and maximum in the array of heights (in linear time). ### [problem:479C], [problem:480A] The solution is again greedy. Sort the exams by increasing $a_i$, breaking ties by increasing $b_i$. Let’s consider exams in this order and try to take the exams as early as possible. Take the first exams in this order on the early day ($b_1...

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Educational Codeforces Round 47 [Rated for Div. 2] Hello Codeforces! On [contest_time:1009] Educational Codeforces Round 47 will start. Series of Educational Rounds continue being held as [Harbour.Space University](https://harbour.space/) initiative! You can read the details about the cooperation between [Harbour.Space University](https://harbour.space/) and Codeforces in the <a href="http://codeforces.me/blog/entry/51208">blog post</a>. This round will be **rated for the participants with rating lower than 2100**. It will be held on extented ACM ICPC rules. After the end of the contest you will have 12 hours to hack any solution you want. You will have access to copy any solution and test it locally. You will be given **7 problems** and **2 hours** to solve them. The problems were invented and prepared by Ivan [user:BledDest,2018-07-13] Androsov, Vladimir [user:Vovuh,2018-07-13] Petrov, Maksim [user:Ne0n25,2018-07-13] Mescheryakov, Aslan [user:ag2cidk,2018-07-13] Tamaev and me. Good luck to all participants! ...

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Codeforces Round #540 (Div. 3) Miss Div. 3 rounds? :) &lt;copy-pasted-part&gt; Hello! [contest:1118] will start at [contest_time:1118]. You will be offered 6 or 7 problems with expected difficulties to compose an interesting competition for participants with ratings up to 1600. Probably, participants from the first division will not be at all interested by this problems. And for 1600-1899 the problems will be too easy. However, all of you who wish to take part and have rating 1600 or higher, can register for the round unofficially. The round will be hosted by rules of educational rounds (extended ACM-ICPC). Thus, during the round, solutions will be judged on preliminary tests, and after the round it will be a 12-hour phase of open hacks. I tried to make strong tests &mdash; just like you will be upset if many solutions fail after the contest is over. You will be given 6 or 7 (or 8) problems and 2 hours to solve them. Note that **the penalty** for the wrong submission in this round (and the followin...

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Codeforces Global Rounds 2020: Final Results In 2020, with the support of XTX Markets, 6 rounds of the Codeforces Global Rounds were held. Each round was common for both divisions. All such rounds were rated for all participants. At each such round, 50 brand T-shirts were handed out, and we gave T-shirts to all problem writers! I say a big thank you to XTX Markets (and personally to Yuri Bedny and Alexander Gerko) for supporting Global Rounds. Without your help, we could not host them! I sincerely admire companies like these who come to support and develop the community that some of their employees come from. It will be great if other companies follow the example and also offer their help. We need it! The prizes for the 6-round series in 2020: - In each round, top-100 participants get points according to the [table](https://pastebin.com/QT5sXEaT). - The final result for each participant is equal to the sum of points he gets in the four rounds he placed the highest. - The best 20 participants over all series get...

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Hack me! (Codeforces Round #282 (Div. 2)) Quite delayed, but here we have stats about hacks in [contest:495]. Previous posts can be found [here](http://codeforces.me/search?query=hackme), including [div1](http://codeforces.me/blog/entry/15151). [cut] <h3>Stats</h3> Problem | <small>Successful hacks</small> | <small>Unsuccessful hacks</small> | Other | Sum | <small>Solutions which can be hacked</small> | <small>Accepted solutions</small> | <small> All solutions on final tests</small>| :---:|:---:|:---:|:---:|:---:|:---:| <small> [problem:495A] </small> | 623 (85.58%) | 76 (10.44%)| 29 (3.98%) | 728 | 47 (2.65%) | 1727 (97.35%) | 1774 | <small> [problem:495B] </small> | 274 (79.42%) | 60 (17.39%)| 11 (3.19%) | 345 | 232 (27.17%) | 622 (72.83%) | 854 | <small> [problem:495C] </small> | 103 (56.59%) | 75 (41.21%)| 4 (2.20%) | 182 | 426 (64.06%) | 239 (35.94%) | 665 | <small> [problem:495D] </small> | 0 | 0 | 0 | 0 | 3 (27.27%) | 8 (72.73%)| 11 | <small> [problem:495E] </small> | 0 | 0 | 0 | 0 | 0 | 0 | 0 | <ce...

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Codeforces Round #262 — #264 Statistics (Brief) Brief stats for rounds<br/> [contest:460]<br/> [contest:461]<br/> [contest:462]<br/> [contest:463] [cut] : ## Codeforces Round #262 (Div. 2) #### First accepted: **A** (00:01) [user:Birjik,2014-08-19] [user:E.K.Goharshady,2014-08-19] [user:Mihai22e,2014-08-19] [user:Slyusar,2014-08-19] [user:VladaMG98,2014-08-19] [user:add1ctus,2014-08-19] [user:dcms2,2014-08-19] [user:linjek,2014-08-19] <br/> **B** (00:07) [user:linjek,2014-08-19] [user:wao.uchiha,2014-08-19] <br/> **C** (00:11) [user:GFW_sb,2014-08-19] <br/> **D** (01:03) [user:quanbuwolaifuze,2014-08-19] <br/> **E** (01:34) [user:jellygendut,2014-08-19] <br/> #### Total hack attempts: +598:-274 #### Top-5 hackers: **1000** [user:Honour_00,2014-08-19] +10:-0 <br/> **1000** [user:VladaMG98,2014-08-19] +11:-2 <br/> **850** [user:linjek,2014-08-19] +10:-3 <br/> **800** [user:KingTon,2014-08-19] +8:-0 <br/> **800** [user:pk.,2014-08-19] +8:-0 <br/> ![ ](https://lh4.googleusercontent.com/-7WamkVz2llM/VAtzu1nF...

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Hack me! (Codeforces Round #283 (Div. 2)) Hey there! Here are the hacking statistics from [contest:496]. It wasn't very good round for hackers (especially because of strong pretests), but still &mdash; let's take a quick look. (Hacks description will be added later, sorry). Previous posts can be found [here](http://codeforces.me/search?query=hackme), including [div. 1](http://codeforces.me/blog/entry/15248). [cut] <h3>Stats</h3> Problem | <small>Successful hacks</small> | <small>Unsuccessful hacks</small> | Other* | Sum | <small>Solutions which can be hacked</small> | <small>Accepted solutions</small> | <small> All solutions on final tests</small>|<small>Hackers efficiency**</small>| :---:|:---:|:---:|:---:|:---:|:---:|:---:| <small> [problem:496A] </small> | 0 (0.00%) | 27 (55.10%)| 22 (44.90%) | 49 | 18 (0.81%) | 2193 (99.19%) | 2211 | 0.00% | <small> [problem:496B] </small> | 3 (8.57%) | 19 (54.29%)| 13 (37.14%) | 35 | 78 (6.67%) | 1091 (93.33%) | 1169 | 3.70% | <small> [problem:496C] </small> | 5 (11....

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School Individual Contest #1 (WCS 2010/11) - Codeforces Beta Round #38 (ACM-ICPC Rules) Hello everybody.<br><br>I would like to invite you to&nbsp;<span class="wl-st" id="wl-st-number1"></span><span class="dct-tt">participate</span> in a new competition, that will be held on the 30th of October at 16:00 MSK. It will be a part of the series of winter programming school olympiads, but it will be only a standart Codeforces round for adult participants.<br><br>Teams aren't invited, only single members. The official rules will be ACM-ICPC.<br>Jury has decided to increase the duration of the competition, which will be <b>4 hours</b> long.<br><br><h3>Attention: <span class="comment-content-13116">People, who <span class="comment-content-13113">are considered out of competition, are participants of </span>Codeforces Round #38, others are participants of School Personal Contest #1. But we will use<b> <u><i>merged result table</i></u></b> for updating rating.</span></h3><br>The authors are me, Mike Mirzayanov and Artem Rakhov. Also I'm expressing <span class="dct-tt">gratitude to <...

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Codeforces Round #274 Greetings to the Codeforces community! Yet another Div1+Div2 round will take place this Sunday, 19th of October at [13:00 MSK](http://timeanddate.com/worldclock/fixedtime.html?day=19&month=10&year=2014&hour=13&min=00&sec=0&p1=166). The round is based on the problems of the regional stage of All-Russia team school competition, which will take place at the same time in Saratov. We are aware about the overlapping with Opencup, but we have no option to shift the round, because we are bounded to the local event. The problems were prepared by [user:HolkinPV,2014-10-18], [user:gridnevvvit,2014-10-18], [user:dans,2014-10-18], [user:Avalanche,2014-10-18], [user:IlyaLos,2014-10-18], [user:Fefer_Ivan,2014-10-18] and me. Scoring: **500-1000-1500-2000-2500** (both divisions). **UPD**: [Editorial](http://codeforces.me/blog/entry/14351) is published.

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Codeforces Global Rounds 2019: Current Results After Four Rounds In 2019, with the support of XTX Markets, 6 rounds of the new Codeforces Global Rounds will be held. These will be common rounds for both divisions of 7–9 problems each. The duration of the rounds will be 2-3 hours, depending on the number and complexity of the problems. All such rounds will be rated for all participants. <i>At each such round, 50 brand T-shirts will be handed out, and we will be happy to give T-shirts to all authors and problem testers.</i> The prizes for the 6-round series in 2019: - In each round top-100 participants get points according to the [table](https://pastebin.com/QT5sXEaT). - The final result for each participant is equal to the sum of points he gets in the four rounds he placed the highest. - The best 20 participants over all series get sweatshirts and place certificates. Current standings after four rounds: | Place | Contestant | = | Round 1 | Round 2| Round 3 | Round 4 | | - | - | - | - | - | - | - | | 1 | [user:tourist,2019-07-21] | 241...

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List of Problems Having Short Statements (800 to 1500) ## List of Problems Having Short Statements (800 to 1500) Long, wordy statements can be exhausting, especially for beginners. So here is a list of problems with **short and easy-to-read statements** in the **800–1500** range, a companion to [Abdullah500's list for 1600–3000](https://codeforces.me/blog/entry/146051). **Notes:** - Every problem here has a statement of **under 1000 characters** (input/output and samples not counted). - Within each rating, problems are listed in order of problem ID, **not** sorted by statement length. - Ratings are as of April 2026 and may shift a little over time. - Short statement does not always mean an easy idea. Some of these are tricky! - The data comes from [alwa97/codeforces-1000](https://github.com/alwa97/codeforces-1000). Many thanks to the author. I picked about 50 problems per rating from there, so check that repo if you want even more. **800** 1. [41A &mdash; Translation](https://codeforces.me/problemset/problem/41/A) 2. [5...

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Teams going to Gwalior/Pune Regionals **UPDATE:** I've uploaded the code that I used to generate this on Github, in case someone needs to generate something similar: [Codeforces Team Rating Calculator](https://github.com/abdullah768/Codeforces-Team-Rating-Calculator) The regional round has ended and here's the final Ranklist: https://www.codechef.com/public/rankings/ACM18GWR Inspired by the list of teams going to Kharagpur regionals, I decided to make one for Gwalior/Pune regionals. The list contains all the teams from the official Gwalior website. If you know the usernames of members of any of the teams. Please update the excel file: ### [HERE] (https://docs.google.com/spreadsheets/d/1jRvwzQzp1DOcazgI7jXBB8uY3u7Ze_eQ77Xa75_Q810/edit?usp=sharing) Team rating calculation has been done according to the official Codeforces team rating calculation formula. The table will be updated with details from the excel file every 6 hours or so. Last Updated: 10 pm, 12th December IST | No. | AIR | Team Name ...

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First Ever Users to Reach Some Rating Milestones Revised: ratings below 1500 and greatest rises Several days ago I published a [table](https://codeforces.me/blog/entry/104320) with first people to reach certain ratings. It featured only ratings above 1500, and [user:adamant,2022-07-09] advised to do the same, but on achieving ratings below 1500. I found it quite interesting, and, after several days of collecting data about participations of 447911 Codeforces users, I finally made this table. [cut] For several reasons I firstly put another table. This is the table of greatest rating rises in the history of Codeforces. The reasons are: 1. I have collected so much data from Codeforces that it would be blasphemy not to use it in as many ways as possible. 2. These tables might intersect a lot: it's easier to get a terrific rise in ratings if you are low-rated. (Many people abuse this and deliberately get very low-rated to make a great jump.) 3. Someone recently posted a table with greatest rating rises and falls. I wasn't able to find this table to check whether it was...

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