Codeforces Round #501 (Div. 3) <copy-pasted-part> Привет! В [contest_time:1015] начнётся [contest:1015] — очередной Codeforces раунд для третьего дивизиона. В этом раунде будет 6 или 7 задач, которые подобраны по сложности так, чтобы составить интересное соревнование для участников с рейтингами до 1600. Наверное, участникам из первого дивизиона они будут совсем не интересны, а для 1600-1899 покажутся простыми. 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. Я постарался сделать приличные тесты — так же как и вы буду расстроен, если у многих попадают решения после окончания контеста. Вам будет предложено 6 или 7 задач и 2 часа на их решение. **Штраф** за неверную попытку в этом раунде (и последующих Div. 3 раундах) будет равняться **10 минутам**. ...

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Codeforces Round #FF Statistics [contest:446] and [contest:447] round statistics [cut] : ### Div. 1 #### First accepted: **A** (00:03) [user:Myungwoo,2014-07-12] [user:sevenkplus,2014-07-12] <br/> **B** (00:14) [user:anta,2014-07-12] <br/> **C** (00:30) [user:vepifanov,2014-07-12] [user:ztxz16,2014-07-12] <br/> **D** (01:23) [user:gchebanov,2014-07-12] [user:vepifanov,2014-07-12] <br/> #### Total hack attempts: +102:-101 #### Top-7 hackers: **600** [user:__tutankhamun__,2014-07-12] +6:-0 <br/> **400** [user:subscriber,2014-07-12] +4:-0 <br/> **350** [user:Reimu,2014-07-12] +4:-1 <br/> **300** [user:cxlove,2014-07-12] +4:-2 <br/> **300** [user:espr1t,2014-07-12] +7:-8 <br/> **300** [user:RAVEman,2014-07-12] +3:-0 <br/> **300** [user:JuanMata,2014-07-12] +3:-0 <br/> #### Other info <br/> [Complete Results](https://lh4.googleusercontent.com/-QHdYExkgKVM/U8NbyJ3kgfI/AAAAAAAACE8/q5Z1MZfhrqQ/...

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Codeforces Round #560 (Div. 3) I have nothing to say this time, so meet yet another Div. 3 round :) &lt;almost-copy-pasted-part&gt; Hello! [contest:1165] will start at [contest_time:1165]. You will be offered 6 or 7 problems (or 8) 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*...

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The most upvoted rounds on Codeforces The top10 of them: | Rank | ID | Name | Upvotes | | :--: | :--: | :----------------------------------------------------------: | :----------------------------------------------------------: | | 1 | 913 | [Hello 2018](/contest/913) | [<span style="font-weight:bold;color:green">+2848</span>](/blog/entry/56954) | | 2 | 773 | [VK Cup 2017 &mdash; Round 3](/contest/773) | [<span style="font-weight:bold;color:green">+2247</span>](/blog/entry/51867) | | 2 | 806 | [Codeforces Round #412 (rated, Div. 1, based on VK Cup 2017 Round 3)](/contest/806) | [<span style="font-weight:bold;color:green">+2247</span>](/blog/entry/51867) | | 2 | 807 | [Codeforces Round #412 (rated, Div. 2, base on VK Cup 2017 Round 3)](/contest/807) | [<span style="font-weight:bold;color:green">+2247</span>](/blog/entry/51867) | | 3 | 10...

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Topics Problems Good Day to you! While a lot of us, when he begins to start competitive programming he found difficult to found problems on some topics in the beginning to practice of it, and same thing for a lot of ICPC Communites that they have started. These are some topic not advanced and videos, problems and articles on them. <br> <spoiler summary="Prefix Sum & Frequency Array"> [Wonderful Coloring](https://codeforces.com/contest/1551/problem/B1) [Do Not Be Distracted](https://codeforces.com/contest/1520/problem/A) [Letter](https://codeforces.com/problemset/problem/43/B) [Pangram](https://codeforces.com/problemset/problem/520/A) [Andryusha and Socks](https://codeforces.com/contest/782/problem/A) [Count Numbers](https://codeforces.com/group/c3FDl9EUi9/contest/262795/problem/A) [Count Characters](https://codeforces.com/group/c3FDl9EUi9/contest/262795/problem/B) [Range Sum Query](https://codeforces.com/group/c3FDl9EUi9/contest/262795/problem/E) [Count a's](https...

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Code leaked in round 446 I participated round 446, after system test, system tell me my [submission:32403500] coincide with [submission:32404737]. The code is surprisingly similar, however I can prove it was written by me. When I see [problem:891C], I remember a similar one [problem:160D], so I refer to my own solution [submission:4398082]. It is easy to see that [submission:32403500] and [submission:4398082] are quite similar at some parts of the code, especially in the beginning of the code and in the beginning of the main. Some variable defined in [submission:32403500] is unused, because they just come from [submission:4398082]. Please explain how to get my code:)--[user:LZYACMR,2017-11-17]

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Codeforces Global Rounds 2020: Current Results (GR7-GR9) 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 three rounds (sorted by total points in three rounds): | Place | Contestant | = | GR 7 | GR 8 | GR 9| |--|--|--|--|--|--| ...

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Hack me! — Year 2014 in review! (part 1.) Hey there! Since new year is coming, I want to start little summing-up of the ending one (of course we still talk about hacks :)). I wrote another short script, which purpose was to summarize all hacks in the 2014. I wanted to upload it after two last rounds, but mostly because of little differences (especially between first and second place), I did it before last rounds. Maybe the next rounds will be more exciting because of it. Below there is a list of 50 best hackers in this year <s>(so far)</s>, the full list can be found [here](http://test.weaselcrow.com/pro/cf/hack2014/). <strong>Update: </strong> After last round, the ranking was updated. The last round was decisive: [user:mosiomohsen,2014-12-31] made 5 successful hacks and 1 unsuccessful and with 450 points, he managed to surpass [user:anta,2014-12-31]. Congratulations! [cut] <div></div> rank | handle | points | best rounds | accuracy | :---:|:---:|:---:|:---:| 1 | [user:mosiomohsen,2014-12-31] | 8...

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Help with a problem from CF round #446 Hi all, I have been trying to solve this problem from CF #446: http://codeforces.com/contest/891/problem/C . The editorial description of this problem is very bare bones ( atleast that is what I feel) and and after numerous hours looking at comments and other submissions, I have failed to come up with a solution that works. Can anybody please provide a brief procedure on how to go about solving this problem? Thanks in advance. And if this is not the way to ask for help here, I apologize as I am quite new to codeforces.

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Suggest making round #618's name interesting Round #618 is going to be held soon. I suggest making the round's name interesting, i.e. Codeforces Round Phi. Number 618, is the first three digits after the decimal point of number phi=(sqrt(5)-1)/2, which is also known as the 'golden section'. And it will be very memorable. See [contest:567] and [contest:446] and [contest:447] as an example.

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Hack me! — Year 2014 in review! (part 2.) Merry Christmas everyone! One round behind us, one more to go in this year. It's time for the second part of my little summing-up (last post can be found [here](/blog/entry/15326)). Now we will show all most accurate hackers. We will count the accuracy as the: $$\frac{\#successfulhacks}{\#allhacks}$$ Because there were a lot of flawless hackers, below we show only hackers with at least 10 successful hacks &mdash; still there were 36 of them! The full list of hackers' accuracy can be found [here](http://test.weaselcrow.com/pro/cf/ahack2014/). Also, below this table there is updated list of best hackers by summarized points, also the full list was updated [here](http://test.weaselcrow.com/pro/cf/hack2014/). [cut] <div></div> ### Accuracy rank | handle | accuracy | best rounds | points | :---:|:---:|:---:|:---:| 1 | [user:hetanglianyi,2014-12-25] | 100.0% | <small>[contest:462] [+19-0]</small> | 1900 (+19-0) | 2 | [user:bmerry,2014-12-25] | 100.0% | <small>[c...

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Some Statistics About CF Rating Changes (2018/07 update) #### Overview There are 1409603 rating changes in 792 rated contests (by 2018/07/14, including those mentioned in the "Something Weird" section). There are 142117 users with at least one rating change. The overall average of deltas is -6.671139. #### Rating Changes Distribution <img src="https://image.ibb.co/gZjnpJ/hist.png" width="90%"/> <img src="https://image.ibb.co/jejnpJ/hist2.png" width="90%"/> (Well, it looks like a boa constrictor eating an elephant...) #### Top 20 Events: Positive Rating Change <table> <tr> <th>#</th> <th>Who</th> <th>Δ</th> <th>Rating</th> <th style="width: 25em;">Contest</th> </tr> <tr> <td>1</td> <td>[user:Mhammad1,2018-07-16]</td> <td><span style="color:green;font-weight:bold;">+803</span></td> <td><span style="font-weight:bold;" class="user-gray">-22</span> → <span style="font-weight:bold;" class="user-gray">781</span></td> <td>[contest:814]</td> </tr> <tr> <td>2</td> <td>[user:white_1,2018-07-16]</td> <td><span style=...

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Codefroces Rating I participated in round 446 and gained +73 rating so I became pupil from newbie . when I checked my rating today . it is the same but the color is grey and my title still newbie , also the contests are not in the contests that I participated in . Is anyone facing similar problem ? [UPD] it is fixed now .

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Round #726 Div 2 Problem C : wrong answer jury found a greater difficulty: jury has 446, participant has 445 (test case 6) Can someone help me understand the meaning of error message that I am getting [here](https://codeforces.com/contest/1537/submission/119890124)

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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.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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