Codeforces Round #270 Do you want to win a T-shirt? Do you want to learn how to design tasks for programming contest? Do you want to solve 7 tasks in 2.5 hours? So Codeforces Round #270 is right for you. It was designed by me in California, Assembled in polygon (so Thank you [user:MikeMirzayanov,2014-09-26] for the system and [user:Gerald,2014-09-26] for organize and testing), will start on [regular time this Sunday](http://www.timeanddate.com/worldclock/fixedtime.html?day=28&month=9&year=2014&hour=19&min=30&sec=0&p1=166), don't miss it! The organizers of **<a href="/blog/entry/13929">Marathon24</a>** decided to present gifts to the best finishers of the round! Best 25 participants will get Marathon24 tshirts! Thanks! <center> <img src="http://www.elmostshirts.com/images/tshirts.jpg"/> <br><small>It is just an image to attract your attention. Real tshirts will be designed specially for Marathon24!</small> </center> There are some articles introduced how to become a problem setter, like [Pro...

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Codeforces Round #290 Fox Ciel is back! I invite you to participate in Codeforces Round #290, which will start at the [standard time on next Monday](http://www.timeanddate.com/worldclock/fixedtime.html?day=2&month=2&year=2015&hour=19&min=30&sec=0&p1=166): This is my 4th round on Codeforces, my previous rounds: [#190](http://codeforces.me/blog/entry/8163), [#228](http://codeforces.me/blog/entry/10605), [#270](http://codeforces.me/blog/entry/13997). Last Div1 Round ([#286](http://codeforces.me/blog/entry/15842)) is so hard, so after notice that, we decide to reduce the difficulty of this round. (For example, current Div1-E was used as Div1-D) I hope more people can enjoy all tasks in this round: this time no task requires advanced knowledge like linear space or Fourier Transform. The background story will be Fox Ciel's life: learning programming, play games, traveling, have dinner and so on. Like Round [#228](http://codeforces.me/blog/entry/10605), top-20 contestants that are currently at...

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Codeforces Round #270 Editorial [problem:472A] One way to solve this is by bruteforce: there are O(n) different ways to decomose n as sum of two number. If we can check if a number is a prime in O(1) then the whole algorithm can run in O(n). You can use Sieve of Eratosthenes to do the pre-calculation. And another way is try to prove this theorem. The prove is simple: if n is odd number, then 9 and (n-9) is an answer (n-9 is an even number at least 4, so a composite number), and if n is even number, then 8 and (n-8) is an answer (n-8 is an even number at least 4, also must be a composite number). [problem:472B] This task can be solve by greedy: the k people with highest floor goes together, and next k people with highest floor goes together and so on. So the answer is 2 * ((f[n]-1) + (f[n-k]-1) + (f[n-2k]-1) + ...) . It is a bit tricky to prove the correctness of greedy, since people can get off the elevator and take it again. We can give a lower bound of the answer by flow analysis: between floor i ...

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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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Registrations count [statistics] Today (March 19, 2020) first time count of registrations per round became greater than fantastic 18000. To be presice it was 18180 (just one more and it would be palindrome). But only one (!) year ago it became more than 10000, so, it increased almost twice. <s>Yes, we are sick of sports programming and it's contagious.</s> Less words, more pictures:   Three notable things: * March, 2014: [Black day](https://codeforces.me/blog/entry/10683). I've already forgot about it. Now with even with more than 10k participants codeforces has almost no queue in the beginning of contests; * September, 2015: [The Second Revolution of Colors and Titles](https://codeforces.me/blog/entry/20638); * Upper envelope of this graph is combined contest, such as Hello/Goodbye/Global rounds. [cut] Some detailed graphs (count of rounds in brackets):...

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Hack me! (CF Round #270) Welcome after the long break in hacks' describtion in [contest:472]. This round had really good pretests, so we didn't have many hacks (81 successful ones), but let's have a look at them. [cut] <h3>Stats</h3> Problem | Successful hacks | Unsuccessful hacks | Other | Sum | :---:|:---:|:---:|:---:|:---:| [problem:472A] | 41 (23.03%) | 105 (58.99%)| 32 (17.98%) | 178 | [problem:472B] | 3 (4.35%) | 52 (75.36%)| 14 (20.29%) | 69 | [problem:472C] | 28 (20.29%) | 38 (27.54%)| 72 (52.17%) | 138 | [problem:472D] | 9 (23.68%) | 19 (50.00%)| 10 (26.32%) | 38 | [problem:472E] | 0 | 0 | 0 | 0 | [problem:472F] | 0 | 0 | 0 | 0 | [problem:472G] | 0 | 0 | 0 | 0 | <center> <img alt="Here should be graph." src="http://www.weaselcrow.com/cfhacks/472a.png" width="100%"> </center> <h3>Description of hacks</h3> [problem:472A] There were no particular errors, most of the hacks were just using some easy to check errors: like using 1 as composite number, bad checking if numbe...

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Codeforces Round 1040 (Div. 1, Div. 2) Editorial Thank you for participation and we hope you enjoy this round :) <spoiler summary="How did you find the contest?"> - Great: - Good: - Average: - Bad: - Trash: </spoiler> <spoiler summary="Which problem is your most favourite?"> - D2A: - D2B: - D1A: - D1B: - D1C1: - D1C2: - D1C3: - D1D: - D1E: - D1F1: - D1F2: </spoiler> <spoiler summary="Which problem you hate the most?"> - D2A: - D2B: - D1A: - D1B: - D1C1: - D1C2: - D1C3: [likes:favorite,2039E3_...

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Educational Codeforces Round 114 [Rated for Div. 2] Hello Codeforces! On [contest_time:1574] [contest:1574] 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 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 [user:adedalic,2021-09-19] Dalabaev, Vladimir [user:vovuh,2021-09-19] Petrov, Ivan [user:BledDest,2021-09-19] Androsov, Mak...

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Experimental Educational Round: VolBIT Formulas Blitz Editorial #### [A. Again Twenty Five!](http://codeforces.me/problemset/problem/630/A) The problem of getting the last two digits is equivalent to the problem of getting the number modulo $100$. So we need to calculate $5^{n} \mod 100$. According to [cut] the rules of modular arithmetic $(a \cdot b) \mod c = ( (a \mod c) \cdot (b \mod c) ) \mod c$ So $5^{n} \mod 100 = ((5^{n-1} \mod 100) \cdot 5) \mod 100$ Let's note that $5^2=25$. Then $5^3 \mod 100 = ((5^2 \mod 100) \cdot 5) \mod 100 = (25 \cdot 5) \mod 100 = 25$ $5^4 \mod 100 = ((5^3 \mod 100) \cdot 5) \mod 100 = (25 \cdot 5) \mod 100 = 25$ And so on. All $5^n \mod 100$ are equal to $25$ for all $n \ge 2$. So to solve the problem one need to just output `25`. There is no need to read $n$. #### [B. Moore's Law](http://codeforces.me/problemset/problem/630/B) Every second the number is multiplied by $1.000000011$. Multiplication several times to the same number is equivalent to exponentiation. So the formula i...

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Second edition of Marathon24 team programming contest Hello everyone!  Once again we invite you to participate in the 24-hour team programming contest **Asseco Programming Marathon24 Gdynia 2014. Powered by CodiLime**. The first edition in 2013 was quite a success: 243 teams of three from over 20 different countries were registered for the contest and 30 teams from 8 countries were qualified for [the finals in Gdynia](http://marathon24.com/gallery/2013/#video). In the contest teams of three can participate. There is no limit concerning the age or education of contestants. Also there is no limit in equipment, programming languages or materials you can use during the contest. The contest consists of two stages. You can check out [problems from the first edition](http://marathon24.com/archive/2013/#qualifications) to familiarize yourself with the format. This year's tasks will also be prepared (among others) by Tomasz Idziaszek [user:monsoon,2014-09-23] and Wojtek N...

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Score distribution in longer contests Hi. In this entry I want to discuss the score distribution and drain of points (by that term I mean how fast points value of problem is becoming smaller) in longer contests (joint ones like #270 or ZeptoLab). In my opinion everything (drain + typical distribution) works fine in regular contests, but not in those longer ones. Due to standard habits adjusted to regular contests, distribution in longer ones (typically 7 tasks with difficulty similar to Div2A, Div2B, Div1A, ..., Div1E and 2,5/3h) is similar to 500-1000-1500-2000-2500-3000-3500. Also, contests are longer, so task submitted in the end of 3h contest is worth only 30% of its original value (drain is 0,4% of original value with every minute, but resulting in not lower value than 30% of original one, even when wrong submissions are taken into account). Then, having accepted problem worth 3500 pts after 2h and 55 mins without any previous wrong submissions is worth 1050 pts, while D submitted after 0,5h is worth 1320pts &mdash...

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Codeforces Round #270 Statistics [contest:472] round statistics [cut] : #### First accepted: **A** (00:01) [user:135678942570,2014-09-27] [user:AkshajK,2014-09-27] [user:KADR,2014-09-27] [user:Lord.of.AMC,2014-09-27] [user:Te4NIK,2014-09-27] [user:Wild_Hamster,2014-09-27] [user:ainu7,2014-09-27] [user:andrewzta,2014-09-27] [user:arknave,2014-09-27] [user:athin,2014-09-27] [user:flashmt,2014-09-27] [user:jonathanirvings,2014-09-27] [user:minimario,2014-09-27] [user:misha.,2014-09-27] [user:ngochai94,2014-09-27] [user:sert,2014-09-27] [user:stevenkplus,2014-09-27] [user:trophies,2014-09-27] <br/> **B** (00:03) [user:tourist,2014-09-27] <br/> **C** (00:06) [user:snuke,2014-09-27] [user:wo_,2014-09-27] <br/> **D** (00:16) [user:aitzhan.askar,2014-09-27] <br/> **E** (01:31) [user:Petr,2014-09-27] <br/> **F** (00:50) [user:PavelKunyavskiy,2014-09-27] <br/> **G** (01:08) [user:AlexDmitriev,2014-09-27] <br/> #### Total hack attempts: +81:-214 #### Top-11 hackers: **400** [user:zetamoo,2014-09-27] +4:-0 <br...

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Разбор Codeforces Round #346 (Div. 2) [659A &mdash; Круглый дом](http://codeforces.me/contest/659/problem/A) Ответом на задачу является формула $((a - 1 + b)$ $mod$ $n$ + $n$) $mod$ $n$ + $1$, где $mod$ $n$ &mdash; операция взятия остатка по модулю $n$. Итоговая временная сложность решения равна $O(1)$. Допускается также итеративное решение, каждый раз перемещающее Васю на 1 подъезд в нужном направлении. Итоговая временная сложность решения равна $O(|b|)$. [659B &mdash; Отбор на олимпиаду](http://codeforces.me/contest/659/problem/B) Будем рассматривать участников каждого региона отдельно. Отсортируем всех участников из региона в порядке невозрастания баллов. Ответ для данного региона неоднозначен тогда и только тогда, когда участников хотя бы трое и баллы второго и третьего участника совпадают. Иначе ответом является пара из первого и второго участников. Итоговая временная сложность решения равна $O(n \log{n})$. [659C &mdash; Таня и игрушки](http://codeforces.me/contest/659/problem/C) Наша зад...

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Infoleague Spring Round 2022 Announcement Hello Codeforces! We would like to invite you to the first (and possibly only) round of Infoleague Spring 2022, the contest starting on Wednesday, March 30th from [12:30 GMT+3](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Infoleague+Spring+2022+Official+Round&iso=20220330T123030&p1=2209&ah=4). The problems in this round have been prepared to train high school students for the upcoming Romanian National Olympiad in Informatics (ONI). **The registration period for this contest starts from [6:30 GMT+3](https://www.timeanddate.com/worldclock/fixedtime.html?msg=Infoleague+Spring+2022+Official+Round+Registration&iso=20220330T0630&p1=2209&ah=6) on Wednesday, March 30th**. This contest has two divisions, Div 1 and Div 2. The Div 2 contest intends to mimic an ONI problemset for 9th and 10th graders, while Div 1 is mainly focused towards challenging 11th and 12th graders. Contest links: [Div1](https://codeforces.me/gym/103634), [Div2](https://codeforces.me/gym/1036...

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Educational Codeforces Round 57 [Rated for Div. 2] Hello Codeforces! On [contest_time:1096] [contest:1096] 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,2018-12-14] Glazov, Adilbek [user:adedalic,2018-12-14] Dalabaev, Vladimir [user:Vovuh,2018-12-14] Petrov, Ivan...

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Some thoughts about Surprise/Unknown Language Rounds I'm a huge fan of Surprise/Unknown Language Round competition format. Theoretically I enjoy participating in them, but in practice I mostly run them. What's so special about them that makes me like them so much? 1. They are unusual. At some point of time (which arrived pretty soon for me) traditional competitions pall and become a blur. If I give it a thought, I can clearly remember only a couple of the 80 SRMS and CF rounds I've done. The SRM which featured MooresLaw problem (great challenge phase and my only ever room win), TCO elimination round which I passed thanks to a last-minute submission on 500pt, a GCJ round from back when it was held on TopCoder platform, when I got stuck at input parsing and never got to the actual solution... and that's all. Marathon memory is a bit better, probably because I've participated in fewer of them, and each match took more time and effort. But unusual competitions leave the most lasting and vivid impression. 2. They fit my skills....

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Notes on Codeforces Beta Round #50, A, B, C(Use Pascal's Triangle to calculate the probability that "at least K events occur among N events") A. Presents This problem can be solved by starting from the 0-th day and implement the following operations. For the i-th day (initially i=0), we check the next K days, i.e., from (i+1)-th to (i+K)-th day. If no holidays are included, we increase the number of presents by one and move to the (i+K)-th day; otherwise we add the number of holidays to the current number of presents and move to the last holiday. Note that if i+K>N, it is sufficient to only count the number of holidays from the i-th day to the N-th day, and add it to the number of presents. B. Cutting Jigsaw Puzzle The solution is straightforward but might be a little complicated to code. At first, we should enumerate all the feasible sizes of pieces. A size with x*y is feasible if x and y are factors of A and B, respectively. For each feasible size x*y, we find out all the pieces and check if there exist any two pieces that are exactly the same. Any two pieces are exactly the same if at least one of the foll...

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Codeforces Round #215 & #216 Statistics Statistics of the rounds (official participants)<br/> [contest:367]<br/> [contest:368]<br/> [contest:369] [cut]:<br/> <pre> <code> --------------------------------------------------------------------------------------------- | Codeforces Round #215 (Div. 1) | --------------------------------------------------------------------------------------------- | | First | Sent | Pretest | Hacked | Systest | Accepted | Attempts | Success | Severity | | | | | failed | | failed | | | % | | --------------------------------------------------------------------------------------------- | A | 00:05 | 639 | 42 | 0 | 2 | 595 | 1170 | 50.9 | 1.83 | | B | 00:08 | 567 | 87 | 35 | 163 | 282 | 1366 | 20.6 | 2.20 | | C | 00:13 | 413 | 73 | 61 | 23 | 256 | 770 | 33.2 | 1.59 | | D | 0...

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Hack me! (Codeforces Round #284 (Div. 1)) Let's take a look at Christmas Round ([contest:498]). Because of not-so-good scheduling, I didn't take part in it ([neither any of my friends did](http://www.test.weaselcrow.com/cfhacks/498-1.png)). In Poland, it is a nice time to spend time with family, not like [this](http://www.test.weaselcrow.com/cfhacks/498-2.jpg). If you are interested how Christmas look like in Poland, check out [polishchristmasguide.com](http://polishchristmasguide.com/). Ok, enough complaining, let's look at the hacks. Previous posts can be found [here](http://codeforces.me/search?query=hackme), including [post for div. 2](/blog/entry/15434). [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:498A] </smal...

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Educational Codeforces Round 64 [Rated for Div. 2] Hello Codeforces! On [contest_time:1156] [contest:1156] 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 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 **7 problems** and **2 hours** to solve them. The problems were invented and prepared by Roman [user:Roms,2019-04-30] Glazov, Adilbek [user:adedalic,2019-04-30] Dalabaev, Vladimir [user:Vovuh,2019-04-30] Petrov, Ivan [user:Bl...

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A2SV G7 — Round #2 Editorial [Here](https://codeforces.me/contests/671638) is the contest link. ### [A1. Non-alternating Deck (easy version)](https://codeforces.me/gym/671638/problem/A1) #### Approach 1 <spoiler summary="Hint 1.1"> Instead of thinking about “alternating every two steps”, define four explicit turns: - Alice1 (current is Alice, next is also Alice) - Alice2 (current is Alice, but next is Bob) - Bob1 (current is Bob, next is also Bob) - Bob2 (current is Bob, but next is Alice) These repeat in a cycle. </spoiler> <spoiler summary="Hint 1.2"> If we encode these states as numbers: - Alice1 = 0 - Alice2 = 1 - Bob1 = 2 - Bob2 = 3 Then after each step: `turn = (turn + 1) % 4` This means if turn < 2, it is Alice's turn else it is Bob's turn. </spoiler> <spoiler summary="Solution 1"> We simulate distributing cards one by one. We maintain: - cards (how many cards will be given in this turn) - cards_given (how many cards we’ve given in this tur...

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A2SV G6 — Round #2 Editorial [Here](https://codeforces.me/contestInvitation/cccd31bebeb08638cc7f11e41ebbd2d9d0a60025) is the link to the contest. All problems are from Codeforces' problemset. #### [A. Make the Product Zero](https://codeforces.me/gym/586960/problem/A) <spoiler summary="Hint"> To make the product of all elements zero, we need at least one element in the array to be zero. </spoiler> <spoiler summary="Solution"> <p> There are three cases to consider: <ul> <li>If there is already a zero in the array, no operations are needed.</li> <li>If there are negative numbers, we can turn one of them into zero, requiring at most |A[i]| operations.</li> <li>If all numbers are positive, the minimum number of operations required is to turn the smallest positive number into zero.</li> </ul> The solution involves iterating through the array and determining the minimum number of operations needed. </p> </spoiler> <spoiler summary="Code1"> ```python3 n = int(input()) ...

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Codeforces Global Rounds 2022: Final Results (GR19-GR24) Hello, Codeforces. It's time to take stock of last year. Shall we begin? And we are happy to sum up the results of the last season of Global Rounds. We announce the results! We remind you that the global rounds are a joint initiative of XTX and Codeforces. We hold 6 such rounds per year. All of them are open to both divisions. At each such round, 50 brand T-shirts were handed out, and we are happy to give T-shirts to all problem authors. The prizes for the 6-round series are: - 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. [cut] The final standings after six rounds (sorted by total points in four best-placed rounds): | Place | Contestant | = | GR 19 | GR 20 | GR 21 | GR 22 | GR 23 | GR 24| |--|--|--|--|...

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【LGR-212-Div.2】Luogu Round 212 Announcement We will hold Luogu Round 212 on Luogu. **This is a Div.2 Round and English statement will be provided officially.** - Contest URL: <https://www.luogu.com.cn/contest/187568> - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?iso=20241229T1400&p1=237> - Duration: 270 minutes - System: IOI - Difficulty: Div.2 - Staffs: [user:Coffee_zzz,2024-12-25], [user:rui_er,2024-12-25], [user:wyrqwq,2024-12-25], [user:IwannaEATaCUTEcaca-qwq,2024-12-25], [user:frostaur_,2024-12-25], [user:N_z__,2024-12-25], [user:shiqingbaiya666,2024-12-25], [user:McIron233,2024-12-25], [user:andychen2012,2024-12-25], [user:Wf_yjqd,2024-12-25], [user:_saixingzhe_,2024-12-25], [user:E.Space,2024-12-25] - Rated range: <=2000 rating on Luogu - Score Distribution: 100-100-100-100 We are looking forward to your participation! English statement will be provided officially. - [A tutorial on using Luogu](https://codeforces.me/blog/entry/131261) - [A brief introduction...

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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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【MX-X1】Mengxiong Weekly · X Round 1 |「KDOI」Round 5 (Synchronous) Announcement We will hold 【MX-X1】梦熊周赛 · 未来组 1 |「KDOI」Round 5（同步赛）(which is a synchronized contest on the newly emerging online judge MXOJ, and problems are provided by the group KDOI) on Luogu. - Contest URL: https://www.luogu.com.cn/contest/179392 - Start Time: https://www.timeanddate.com/worldclock/fixedtime.html?iso=20240707T1400&p1=237 - Duration: 270 minutes - System: IOI - Difficulty: Codeforces (Div. 1+2) - Writer: [user:sszcdjr,2024-07-06], [user:Otomachi_Una,2024-07-06], [user:Error_Yuan,2024-07-06]. - Tester: [user:sszcdjr,2024-07-06], [user:Otomachi_Una,2024-07-06], [user:Error_Yuan,2024-07-06], [user:Ternary_Tree_,2024-07-06], [user:wyrqwq,2024-07-06], [user:275307894a,2024-07-06], [user:A_zjzj,2024-07-06]. - Coordinator: [user:hualian,2024-07-06]. - Rated range: for all - The point values: 100-100-100-100-100-100. We are looking forward to your participation! If you cannot understand Chinese, ChatGPT may be helpful. UPD: The original contest (on MXOJ) can be visited [...

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JRKSJ Round 9 &「KDOI」Round 7 Announcement We will hold JRKSJ Round 9 &「KDOI」Round 7 on Luogu. This is a high-quality unofficial contest on Luogu. - Contest URL: - Div. 1: https://www.luogu.com.cn/contest/167920 - Div. 2: https://www.luogu.com.cn/contest/187338 - Start time: https://www.timeanddate.com/worldclock/fixedtime.html?iso=20240815T1400&p1=237 - Duration: 270 minutes - System: IOI - Difficulty: Similar to the last 4 problems of Codeforces Div. 1/2 (respectively) - Writer: [user:wyrqwq,2024-08-13], [user:sail_with_pleasure,2024-08-13], [user:Otomachi_Una,2024-08-13], [user:dqstz,2024-08-13], [user:sszcdjr,2024-08-13] - Tester: [user:cyffff,2024-08-13] and above. - Special thanks to [user:orzdevinwang,2024-08-13] for developing some of the problems. - Rated range: Div. 2 is rated for those whose Luogu rating less than 2200. Div. 1 is rated for all. - Score Distribution: 100-100-100-100-100-100. We are looking forward to your participation! If you cannot understand Chinese, ChatGPT may be helpful. W...

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Codeforces Global Rounds 2021: Final Results (GR13-GR18) Tomorrow will be the first global round of this year. And we are happy to sum up the results of last season. We announce the results! We remind you that the global rounds are a joint initiative of XTX and Codeforces. We are happy to announce that they continue into the new year. We hold 6 such rounds per year. All of them are open to both divisions. At each such round, 50 brand T-shirts were handed out, and we are happy to give T-shirts to all problem authors. The prizes for the 6-round series are: - 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. The final standings after six rounds (sorted by total points in four best placed rounds): | Place | Contestant | = | GR 13 | GR 14 | GR 15 | GR 16 | GR 17 | GR 18| |--...

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the errorgorn interview After a few months break from interviews, we're back with some interesting discussions. I have recorded 4 interviews since the last published one and will be releasing them in the near future. First one is a great discussion with [user:errorgorn,2025-08-14]. He's a two time IOI gold medalist, an LGM and of course a great contributor to the community through his round coordination and blogs (which shows on the contribution ranklist!). Listen in to hear about his coordinating philosophy and his journey through competitive programming. <center> <iframe width="480" height="270" src="https://www.youtube.com/embed/fMEeE-Icjv4"> </iframe> </center> Our previous podcasts in case you missed them: - <div style="color:red; display:inline;"> <b>Pajaraja</b></div>: https://youtu.be/ax4xjGBda-o - <div style="color:red; display:inline;"> <div style="color:black; display:inline;"><b>R</b></div><b>adewoosh</b></div>: https://youtu.be/F7sTxKfx5VU - <div style="color:red; display:inline;">...

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Notes on Codeforces Beta Round #48, A, B, C(Precision-guaranteed Binary Search), D(Prefix and Suffix idea) A. Cheaterius's Problem We can adopt a linear array a[4] to denote any 2*2 square, with a[0] being the upper left cell, a[1] being the upper right cell, a[2] being the bottom left cell and a[3] being the bottom right cell. Then, the rotation of 0, 90, 180 and 270 degrees can be viewed as a circular shift of array a[4], with length of 0, 1, 2 and 3. Therefore, for any two squares, they are exactly the same if one of them can be obtained by implementing a circular shift with some length to the other one. B. bHTML Tables Analisys One can check that whenever we meet a '</td>', it means that we have met a new cell. Thus, we can adopt a variable S to count the number of cells that we have met. Note that when we detect a '</table>', it means that all the cells that we have counted should belong to this table. Therefore, we can store the current value of S, and set it to zero again, since the following cells, if there are any, should belong to some other table. C. Three Base Stati...

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Codeforces Global Rounds 2021: Current Results (GR13-GR17) In 2021 (as in 2019 and 2020), with the support of XTX Markets, 6 rounds of the new Codeforces Global Rounds are held: common rounds for both divisions of 7–9 problems each. The duration of the rounds is 2-3 hours, depending on the number and complexity of the problems. All such rounds are rated for all participants. <i>At each such round, 50 brand T-shirts are handed out, and we are happy to give T-shirts to all problem authors.</i> The prizes for the 6-round series in 2021: - 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 five rounds he placed the highest. - The best 20 participants over all series get sweatshirts and place certificates. Current standings after five rounds (sorted by total points in four best placed rounds): | Place | Contestant | = | GR 13 | GR 14 | GR 15 | GR 16 | GR 17| | - | - | - | - | - | - | - | - | | ...

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【LGR-272】Luogu Round 272 Announcement We will hold Luogu Round 272 on Luogu. This is a Div.2 round. English statement will be provided officially. You can click the button to change language.  - Contest URL: <https://www.luogu.com.cn/contest/299754> - Start Time: [02.21 14:00(UTC+8)](https://www.timeanddate.com/worldclock/fixedtime.html?iso=20260221T1400&p1=237) - Duration: 270 minutes - System: IOI - Difficulty: CF Div.2 - Staffs: [user:zyc070419,2026-02-20], [user:ysparkle,2026-02-20], [user:39xiemy,2026-02-20], [user:Ybll_,2026-02-20], [user:ericzc,2026-02-20], [user:Green_Leaves,2026-02-20] - Rated range: <=2000 rating on Luogu - Score distribution: 100-100-100-100-100 We are looking forward to your participation! - [A tutorial on using Luogu](https://codeforces.me/blog/entry/131261) (Please note that `#pragma GCC optimize` is temporarily banned for some reason on Luogu.) ...

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【MX-X2】Mengxiong Weekly (Open) We will hold 【MX-X2】Mengxiong Weekly (Open) on Luogu. This is a **Div. 1+2** round provided by our collaborator. If you cannot understand Chinese, ChatGPT may be helpful. - Contest URL: https://www.luogu.com.cn/contest/188966 - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?msg=MX-S2&iso=20240810T1330&p1=237> - Duration: 270 minutes - System: IOI - Difficulty: Div. 1+2 - Writer & Tester: [user:Ternary_Tree_,2024-08-08], [user:SpadeA261,2024-08-08], [user:McIron233,2024-08-08], [user:Nahidameow,2024-08-08], [user:A_zjzj,2024-08-08], [user:275307894a,2024-08-08], [user:AK-Dream,2024-08-08], [user:Coffee_zzz,2024-08-08], [user:rui_er,2024-08-08], [user:shiqingbaiya666,2024-08-08] - Rated range: **Unrated on Luogu** - The points value: TBD We are looking forward to your participation! If you cannot understand Chinese, ChatGPT may be helpful. We are working on establishing an English platform, but it takes time. We plan to complete this ...

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【MX-X8/J10】Mengxiong Weekly (Open, Div.1+Div.3) We will hold 【MX-X8/J10】Mengxiong Weekly (Open) on Luogu. This is a Div.1+Div.3 round provided by our collaborator. If you cannot understand Chinese, ChatGPT may be helpful. - Contest URL: - Div.1: <https://www.luogu.com.cn/contest/226531> - Div.3: <https://www.luogu.com.cn/contest/226532> - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?iso=20250131T1330&p1=237> - Duration: 270 minutes - System: IOI - Difficulty: Div.1+Div.3 - Staffs: [user:Otomachi_Una,2025-01-10], [user:251Sec,2025-01-10], [user:wyrqwq,2025-01-10], [user:wsc2008qwq,2025-01-10], [user:AK-Dream,2025-01-10], [user:StarSilk,2025-01-10] - Rated Range: Unrated on Luogu - Score Distribution: - Div.1: 100-100-100-100-100-100 - Div.3: 100-100-100-100-100 - The Div.3C will be Div.1A, Div.3D will be Div.1B, etc. We are looking forward to your participation! If you cannot understand Chinese, ChatGPT may be helpful. - [A tut...

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Codeforces Global Rounds 2020: Current Results (GR7-GR10) In 2020 (as 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 problem authors and problem testers.</i> 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 sweatshirts and place certificates. Current standings after four rounds (sorted by total points in four rounds): | Place | Contestant | = | GR 7 | GR 8 | GR 9 | GR 10| |--|--|--|--|--...

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【MX-X10/J12】Mengxiong Weekly (Open, Div.1+Div.3) We will hold 【MX-X10/J12】Mengxiong Weekly (Open) on Luogu. This is a Div.1+Div.3 round provided by our collaborator. English statement will be provided by DeepSeek R1. You can switch the language of the problem description. - Contest URL: - Div.1: <https://www.luogu.com.cn/contest/237310> - Div.3: <https://www.luogu.com.cn/contest/237311> - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?iso=20250330T1330&p1=237> - Duration: 270 minutes - System: IOI - Difficulty: Div.1+Div.3 - Staffs: [user:sidekick257,2025-03-28], [user:vegetable_he,2025-03-28], [user:ORzyzRO,2025-03-28], [user:cxqghzj,2025-03-28], [user:A_zjzj,2025-03-28], [user:jerryjohn,2025-03-28], [user:Fido_Puppy,2025-03-28], [user:StarSilk,2025-03-28] - Rated range: **Unrated on Luogu** - Score Distribution: - Div.1: 100-100-100-100-100-100 - Div.3: 100-100-100-100-100 - The Div.3C will be Div.1A, Div.3D will be Div.1B, etc. ...

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【MX-X7/J9】Mengxiong Weekly (Open, Div.1+Div.3) We will hold 【MX-X7/J9】Mengxiong Weekly (Open) on Luogu. This is a Div.1+Div.3 round provided by our collaborator. If you cannot understand Chinese, ChatGPT may be helpful. - Contest URL: - Div.1: <https://www.luogu.com.cn/contest/218816> - Div.3: <https://www.luogu.com.cn/contest/218817> - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?iso=20250111T1330&p1=237> - Duration: 270 minutes - System: IOI - Difficulty: Div.1+Div.3 - Staffs: [user:ducati,2025-01-10], [user:sidekick257,2025-01-10], [user:vegetable_he,2025-01-10], [user:DaydreamWarrior,2025-01-10], [user:ORzyzRO,2025-01-10], [user:YuJiahe,2025-01-10], [user:StarSilk,2025-01-10] - Rated Range: Unrated on Luogu - Score Distribution: - Div.1: 100-100-100-100-100-100 - Div.3: 100-100-100-100-100 - The Div.3C will be Div.1A, Div.3D will be Div.1B, etc. We are looking forward to your participation! If you cannot understand Chinese, ...

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Codeforces Round -270: (D. Design Tutorial: Inverse the Problem) — Cannot understand the gravity of the problem !!! [EDIT] It is Codeforces Round &mdash; 270, not SRM-270. Sorry for mixing up with TopCoder! My understanding of [the problem](http://codeforces.me/contest/472/problem/D) as below: A matrix is given where each entry (row,col) represents weight of an edge from row to col. We have to check if the matrix can be represented as a weighted tree. So, I think, there are two things to check. If a node has a positive edge (weight>0) to itself, then it is not a weighted tree. If weight[u,v] != weight[v,u], then it is also not a weighted tree. Are these conditions sufficient? I think NO. But, I am not getting what else should we check. I googled about "weighted tree" to gain some knowledge. I found that it is a tree simply weights are given for every edge. Am I missing something? If anyone can clarify the problem description and the missing parts of my knowledge about weighted tree, I will be grateful! Thanks!

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Notes on Codeforces Beta Round #78, Div2-A, B, C [problem:99A] Using C++, there is a simple manner to implement string parsing. For this problem, we can replace '.' with space, and initialize an 'istringstream' type with this modified string. Then, we define two string variables, and initialize them with 'istringstream' as a standard input. The next work is to find the last digit of the first string and the first digit of the second string, and output the answer according to the requirement. [problem:99B] Take care of two special cases $n=1, 2$. For $n\ge 3$, we can find out the maximum and minimum values, denoted as $min$ and $max$, respectively. Besides, we should find out all the other values that are neither $min$ nor $max$. If such value is unique, and equal to $\frac{max+min}{2}$, the current configuration can be recovered. [problem:99C] The complete permutation has $6!=720$ patterns. Therefore, we can compare every one with all the other ones to check whether it results in a unique pattern or not. Now we should ...

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【MX-X3/J4】Mengxiong Weekly (Open, Div.1+Div.3) We will hold 【MX-X3/J4】Mengxiong Weekly (Open) on Luogu. This is a Div.1+Div.3 round provided by our collaborator. If you cannot understand Chinese, ChatGPT may be helpful. - Contest URL: - Div.1: <https://www.luogu.com.cn/contest/196629> - Div.3: <https://www.luogu.com.cn/contest/196630> - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?iso=20240908T1330&p1=237> - Duration: 270 minutes - System: IOI - Difficulty: Similar to Codeforces Div.1 and Div.3 - Writer & Tester: [user:Const_int,2024-09-07], [user:Ternary_Tree_,2024-09-07], [user:MatrixGroup,2024-09-07], [user:Alan_dong,2024-09-07], [user:Leasier,2024-09-07], [user:wyrqwq,2024-09-07], [user:Sol1,2024-09-07], [user:StarSilk,2024-09-07] - Rated Range: **Unrated on Luogu** - The points value: - Div.1: 100-100-100-100-100-100 - Div.3: 100-100-100-100-100 - The Div.3C will be Div.1A, Div.3D will be Div.1B, etc. We are looking forward to your p...

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【MX-X11/J13】Mengxiong Weekly (Open, Div.1+Div.3) We will hold 【MX-X11/J13】Mengxiong Weekly (Open) on Luogu. This is a Div.1+Div.3 round provided by our collaborator. English statement will be provided by DeepSeek R1. You can switch the language of the problem description.  - Contest URL: - Div.1: <https://www.luogu.com.cn/contest/240581> - Div.3: <https://www.luogu.com.cn/contest/240582> - Start Time: [04-12 13:30 (GMT+8)](https://www.timeanddate.com/worldclock/fixedtime.html?iso=20250412T1330&p1=237) - Duration: 270 minutes - System: IOI - Difficulty: Div.1+Div.3 - Staffs: [user:fantasynumber,2025-04-10], [user:zjdl,2025-04-10], [user:donotmozheng,2025-04-10], [user:ZYPRESSEN,2025-04-10], [user:0x0002,2025-04-10], [user:StarSilk,2025-04-10], [user:Kubic,2025-04-10] - Rated range: **Unrated on Luogu** - Score Distribution: - Div.1: 100-100-100-100-100-100 - Div.3: 100-100-100-100-100 - Th...

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【MX-X5/J6】Mengxiong Weekly (Open, Div.1+Div.3) We will hold 【MX-X5/J6】Mengxiong Weekly (Open) on Luogu. This is a Div.1+Div.3 round provided by our collaborator. If you cannot understand Chinese, ChatGPT may be helpful. - Contest URL: - Div.1: <https://www.luogu.com.cn/contest/198974> - Div.3: <https://www.luogu.com.cn/contest/198975> - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?iso=20240928T1330&p1=237> - Duration: 270 minutes - System: IOI - Difficulty: Similar to Codeforces Div.1 and Div.3 - Writer & Tester: [user:10circle,2024-09-07], [user:QwQwf,2024-09-07], [user:Ender32k,2024-09-07], [user:JWRuixi,2024-09-07], [user:zltzlt,2024-09-07], [user:sinsop90,2024-09-26], [user:flying,2024-09-07] - Rated Range: **Unrated on Luogu** - The points value: - Div.1: 100-100-100-100-100-100 - Div.3: 100-100-100-100-100 - The Div.3C will be Div.1A, Div.3D will be Div.1B, etc. We are looking forward to your participation! If you cannot understand C...

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【MX-X6/J7】Mengxiong Weekly (Open, Div.1+Div.3) We will hold 【MX-X6/J7】Mengxiong Weekly (Open) on Luogu. This is a Div.1+Div.3 round provided by our collaborator. If you cannot understand Chinese, ChatGPT may be helpful. - Contest URL: - Div.1: <https://www.luogu.com.cn/contest/200833> - Div.3: <https://www.luogu.com.cn/contest/200834> - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?iso=20241003T1330&p1=237> - Duration: 270 minutes - System: IOI - Difficulty: Similar to Codeforces Div.1 and Div.3 - Writer & Tester: [user:Sol1,2024-10-02], [user:ChenKaifeng,2024-10-02], [user:A_zjzj,2024-10-02], [user:hhoppitree,2024-10-02] - Rated Range: **Unrated on Luogu** - The points value: - Div.1: 100-100-100-100-100-100 - Div.3: 100-100-100-100-100 - The Div.3C will be Div.1A, Div.3D will be Div.1B, etc. We are looking forward to your participation! If you cannot understand Chinese, ChatGPT may be helpful. We are working on establis...

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【MX-S5】Mengxiong Weekly(Open, Div.1.5) We will hold 【MX-S5】Mengxiong Weekly (Open) on Luogu. This is a "Div.1.5" round provided by our collaborator. If you cannot understand Chinese, ChatGPT may be helpful. This contest is a **simulation test** for Chinese NOIP, which is the provincial competitive programming contest for Chinese middle school students and is a must-participate contest for them. At least 7620 participants will attend NOIP this year. This contest is **not full-feedback**. You will not receive the results during the contest, and the score of each problem is only dependent on your last submission. - Contest URL: <https://www.luogu.com.cn/contest/211087> - Start Time: <https://www.timeanddate.com/worldclock/fixedtime.html?iso=20241109T0830&p1=237> - Duration: 270 minutes - Difficulty: similar to NOIP, which is similar to "Div.1.5" - Writer & Tester: [user:275307894a,2024-11-08], [user:lizhous,2024-11-08], [user:Kares,2024-11-08], [user:YuJiahe,2024-11-08], [user:Otomachi_Una,2024-11-08],...

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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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Codeforces Round #270 div ?! Hello ! Codeforces Round #270 for which division? no division (:p) or both of them :) ?! **UDP:** and **unusual** duration (2:30) **why?!** is there any **surprise ?**

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The entire cses problem set sorted by the number of solvers! I could not find it online so I made it myself, I hope you will find it useful! Problem : Number of solvers - Weird Algorithm : 73338 - Missing Number : 62177 - Repetitions : 54281 - Increasing Array : 50436 - Permutations : 44614 - Distinct Numbers : 33154 - Dice Combinations : 32886 - Number Spiral : 31522 - Bit Strings : 29957 - Minimizing Coins : 28281 - Trailing Zeros : 28124 - Coin Combinations I : 26104 - Two Sets : 25446 - Coin Piles : 24696 - Apartments : 24318 - Removing Digits : 24291 - Two Knights : 23643 - Grid Paths : 23168 - Ferris Wheel : 23109 - Counting Rooms : 22561 - Palindrome Reorder : 22339 - Coin Combinations II : 22133 - Sum of Two Values : 21004 - Maximum Subarray Sum : 20797 - Book Shop : 20376 - Creating Strings : 19359 - Building Roads : 19197 - Restaurant Customers : 18982 - Concert Tickets : 18507 - Apple Division : 18503 - Stick Lengths : 18339 - Movie Festival : 17839 - Message Route : 16337 - Building Teams : 1578...

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Mail.Ru Cup 2018 — Results of R1+R2+R3 Here are merged results of [contest:1054], [contest:1055] and [contest:1056] according to the GP100 scores (see the announcement for the details https://codeforces.me/blog/entry/62355). Best two contests give the summary score of a participant. This table is unofficial yet. But anyway... congratulations to the winnerzzzz! | Place | Contestant | = | Round 1 | Round 2 | Round 3| | - | - | - | - | - |-| | 1 | [user:mnbvmar,2018-11-25] | 1497 | 1000 | 497 | 29 | | 2 | [user:V--o_o--V,2018-11-25] | 1281 | 575 | 575 | 706 | | 3 | [user:Radewoosh,2018-11-25] | 1265 | &mdash; | 265 | 1000 | | 4 | [user:aid,2018-11-25] | 1204 | 204 | 1000 | 142 | | 5 | [user:LHiC,2018-11-25] | 1203 | 497 | 706 | 226 | | 6 | [user:Um_nik,2018-11-25] | 997 | 706 | 291 | 235 | | 7 | [user:ksun48,2018-11-25] | 788 | 291 | &mdash; | 497 | | 8 | [user:SpyCheese,2018-11-25] | 742 | 371 | 371 | 265 | | 9 | [user:RAVEman,2018-11-25] | 619 | 19 | 176 | 443 | | 10 | [user:scott_wu,2018-11-25] | 614...

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Ratings issue Ehm, what happened, did the rating changes at round #270 got deleted?

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Geometry: Polygon algorithms I decided to share my implementations for the basic polygon algorithms. I see almost no problems on this topic and I hope this will change in the future. First, let's remind the definitions we will use: 1. **Polygon** is a plane figure that is bounded by a finite chain of straight line segments closing in a loop to form a closed chain or circuit. These segments are called its edges or sides, and the points where two edges meet are the polygon's vertices or corners ([wiki](https://en.wikipedia.org/wiki/Polygon)). 2. Polygon is **convex** if a line segment connecting any two points on its boundary lies inside the polygon. Equivalently, all its interior angles are less than or equal to 180 degrees. 3. Polygon is **strictly convex** if in addition no three vertices lie on the same line. Equivalently, all its interior angles are less than 180 degrees. 4. Polygon is **simple** if its boundary doesn't cross itself. I will present two algorithms for each problem: one for **ar...

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Codeforces Round #270 Do you want to win a T-shirt? No , I dont . Do you want to learn how to design tasks for programming contest? No , I dont . Do you want to solve 7 tasks in 2.5 hours? No , I dont. So Codeforces Round #270 is not right for me. Have a nice day.

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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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