Codeforces Round #925 (Div. 3) Привет! В [contest_time:1931] начнётся [contest:1931] — очередной Codeforces раунд для третьего дивизиона. В этом раунде будет 6-8 задач, которые подобраны по сложности так, чтобы составить интересное соревнование для участников с рейтингами до 1600. Однако все желающие, чей рейтинг 1600 и выше могут зарегистрироваться на раунд вне конкурса. Раунд пройдет по правилам образовательных раундов. Таким образом, во время раунда задачи будут тестироваться на предварительных тестах, а после раунда будет 12-ти часовая фаза **открытых взломов**. Мы постарались сделать приличные тесты — так же как и вы, мы будем расстроены, если у многих будут падать решения после окончания контеста. Вам будет предложено **7 задач** и **2 часа 15 минут** на их решение. **Штраф** за неверную попытку в этом раунде будет равняться **10 минутам**. [Напоминаем](https://mirror.codeforces.com/blog/entry/59228), что в таблицу официальных результатов попадут только _достоверные участники третьего дивизиона_. Как напи...

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codeforces Codeforces | In English По-русски pathetique | Logout HOMETOPCATALOGCONTESTSGYMPROBLEMSETGROUPSRATINGEDUAPICALENDARHELP → Pay attention Before contest Educational Codeforces Round 162 (Rated for Div. 2) 2 days Register now » → pathetique pathetique User''s contest rating in Codeforces communityRating: 1448 User''s contribution into Codeforces communityContribution: -61 Settings Blog Favourites Teams Submissions Problemsetting Groups Talks Contests → Top rated # User Rating 1 jiangly 3678 2 Benq 3602 3 ecnerwala 3542 4 maroonrk 3541 5 cnnfls_csy 3540 6 orzdevinwang 3493 7 inaFSTream 3478 8 Um_nik 3430 9 Geothermal 3409 9 Rebelz 3409 Countries | Cities | Organizations View all → → Top contributors # User Contrib. 1 maomao90 174 2 adamant 164 3 TheScrasse 161 3 SecondThread 161 3 awoo 161 6 nor 159 7 maroonrk 158 8 Um_nik 156 9 BledDest 145 9 Geothermal 145 View all → → Favourite groups # Name 1 X-Camp 402H 2022 Fall View all → ...

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Educational Codeforces Round 86 [Rated for Div. 2] Hello Codeforces! On [contest_time:1342] [contest:1342] 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://mirror.codeforces.com/blog/entry/51208">blog post</a>. 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 Roman [user:Roms,2020-04-25] Glazov, Adilbek [user:adedalic,2020-04-25] Dalabaev, Vladimir [user:vovuh,2020-04-25] Petrov, Ivan [us...

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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://mirror.codeforces.com/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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Milestones: ratings below 1500 and greatest rises (2024 edition) <i>Note.</i> This is an updated version of [this post](https://mirror.codeforces.com/blog/entry/104683). If you like [this style](https://mirror.codeforces.com/blog/entry/104320) more, please tell me in the comments. Since [user:tourist,2024-09-05]'s [breakthrough](https://mirror.codeforces.com/blog/entry/133401), I've received a lot of requests to update my old posts with rating achievements. However, I wasn't able to do it immediately since my method of doing it requires to download the rating change history of every user, which, in turn, requires to perform several hundred thousand requests to Codeforces, about which the website (and Cloudflare) is not happy. It took more that three days, but finally the job is done! Below are two tables. The first one is the greatest positive rating changes. The second one is the first users ever to reach some rating value. [cut] <table> <tr> <th>Place</th> <th>&Delta;</th> <th>Person</th> </tr> <tr> <td>1^st</td> <td><b>1182<...

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Invitation to ‘Paradigm Shift 2012’ on Codechef Indian Institute of Technology, Indore is hosting an online programming contest 'Paradigm Shift 2012' on the Codechef platform. http://www.timeanddate.com/worldclock/fixedtime.html?msg=Paradigm+Shift&iso=20120331T18&p1=925&ah=2&am=30. <pre> <b>Details :</b> <b>Date</b> : 31st March 2012 <b>Time</b> : 1800 to 2030 (Indian Standard Time) 1630 to 1900 (Moscow Standard Time) 1430 to 1700 (Central European Summer Time) 0830 to 1100 (Eastern Daylight Time) <b>Sponsored by</b> : IBM <b>Programming Partner</b> : Codechef <b>Prizes</b> : 1st Prize : Apple iPod nano 2nd Prize : Seagate 1 TB HDD Of course, there are Codechef T-shirts to be won besides these. </pre> This contest is open to all. It will be an ACM-ICPC style contest with all problems visible from the start and no hacks. In order to participate, all you have to do is register on http://www.codechef.com/ . (There is no seperate registration for the contest.) After this, log...

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Thoughts on Round 925 (Div. 3) Just finished my first contest after almost a year of no codeforces contests. Overall, I felt like it went pretty alright, although I only managed to solve the first three problems. On problem 4 (Divisible pairs), I got completely stuck for a long time, before finding a solution on the very last minute of the contest, which turned out to be too slow. I find that this scenario happens fairly often: usually I solve two or three problems, which don't take too much time, but then some other problem will stump me and all solutions I come up with either don't work because of some test cases that I didn't think of or it's just too slow. Looking forward to looking at the solution for it though &mdash; I had a suspicion it might involve two pointers from the moment I saw the problem, but I couldn't find any way to implement it. There's only one conclusion that can be drawn from this &mdash; I need to practice more. Well then, 'til the next contest!

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Doubt in codeforces delta calculation I had a doubt regarding the codeforces delta calculation since some time and it would be great if someone could help to clarify it. Suppose there are 2 participants, A and B with A's rating less than B's rating. If participant A performs better or equal to the participant B, then it would be expected that participant A has more positive delta as compared to B since A was expected to perform worse but performed better or equal. But I have noticed previously in some cases and also in the recently held https://mirror.codeforces.com/contest/2127 that this is not the case. Example:  Link: https://mirror.codeforces.com/contest/2127/ratings/page/10#:~:text=925 Could someone help with the confusion. Thanks a lot in advance!

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Yet another advice for struggling greens/greys Abstract ------------------ Suspend participating in Codeforces Rounds for a **long** time (at least a few months). During this time, try to participate in contests on other websites (AtCoder/Luogu/CodeChef or other). After that, when you participate in Codeforces Rounds again, your rating will surprisingly increase (at least for me). Here's why.[cut]Something interesting is that I got this truth from rhythm games. Detail ------------------ Take a look at my rating graph. I was nearly always in green/grey in 2023 before September (accidentally became specialist after an educational round but returned pupil after the next round). I thought the problems in division 2 are too hard for me and I will permanently remain in green/grey. Then I suddenly remember an experience in rhythm game. In February 2023, I was playing a song named Concvssion with the difficulty IN15 in Phigros. I kept getting 1 good, and I tried for many days, but the results were always 1 good. Then I gav...

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Java Solution of D- Divisible Pairs CF Round 925 I attempted the D problem in JAVA 21 64bit with the simple logic of storing the remainder of a[i] in pairs along with their frequency in HashMap and check if (x-(a[i]%x)),(a[i]%y)) is already present, adding 1 to answer if it happens. I also make the remainder equal to x if it comes out to be zero. Heres my solution [My Answer](https://mirror.codeforces.com/contest/1931/submission/246243244) but for some reason it fails the 12th test. I don't know what on God's Earth it is, but I then just convert the same logic to C++ and its accepted. Where am I going wrong? What seems to be the problem here? Is there an alternative? A friend of mine suggested using a 2D array instead of a map an hence saving the trouble of creating pair class in JAVA but I could not fully grasp his concept. Please help me out here.

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Regarding mistake in Div-3 (Round-927) Attention! Your solution 247034903 for the problem 1932D significantly coincides with solutions 247033655 and 247034903. Such a coincidence is a clear rules violation. Note that unintentional leakage is also a violation. For example, do not use ideone.com with the default settings (public access to your code). If you have conclusive evidence that a coincidence has occurred due to the use of a common source published before the competition, write a comment to post about the round with all the details. More information can be found at http://mirror.codeforces.com/blog/entry/8790. Such violation of the rules may be the reason for blocking your account or other penalties. In case of repeated violations, your account may be blocked. Respected Codeforces Community, I have 2 accounts, one being my main ([Algo_Phoenix](https://mirror.codeforces.com/profile/Algo_Phoenix)) and other one is my alternate ([Monkey_d_Luffy-19834098](https://mirror.codeforces.com/profile/Monkey_d_Luffy-19834098)). In Div-3 (Roun...

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Codeforces (Div 1 + Div 2) How you can know at February 17 at 19:35 will be contest for Div 1 and Div 2 and since i wont be there because these will be hard for me(really hard in case that i have only 800 rating) i wish luck for all who will be there but i'll be in Codeforces Round 925 (Div 3) and also wish luck for that too and dont forget too rigistrate before register is clothin like i did in provous Div 3 :D sorry if all this text look silly cause i dont write blogs usually and again good luck

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Blog collection <p>________________________________________________________________________________________<br><br></p><h3><b>Puzzle</b></h3><ul><li><a href="http://mirror.codeforces.com/blog/entry/66">Red and Black hair</a>, </li><li><a href="http://mirror.codeforces.com/blog/entry/112">The 12 chairs and diamonds</a></li><li><a href="http://mirror.codeforces.com/blog/entry/228">Monty Hall Problem</a></li></ul><br><br><h3>Useful <br></h3><ul><li><a href="http://mirror.codeforces.com/blog/entry/70">Petr Mitrichev, 3 days in Sao Paulo Training Camp 2010</a></li><li><a href="http://mirror.codeforces.com/blog/entry/512">Useful links</a></li><li><a href="http://mirror.codeforces.com/blog/entry/529">Problem Set Analysis Of CodeForces</a></li><li><a href="http://mirror.codeforces.com/blog/entry/546">Discussions Of CodeForces Round</a></li><li><a href="http://mirror.codeforces.com/blog/entry/1492">ALL CodeForces rounds Tutorial</a></li><li><a href="http://mirror.codeforces.com/blog/entry/1534">Online Judge Locator</a></li><li><a href="http://mirror.codeforces.com/blog/entry/170...

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