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Educational Codeforces Round 75 [Rated for Div. 2]
Difference between en3 and en4, changed 1,669 character(s)
Hello Codeforces!↵

On [contest_time:1251] [contest:1251] 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.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 **7 problems** and **2 hours** to solve them.↵
 ↵
The problems were invented and prepared by Roman [user:Roms,2019-10-23] Glazov, Adilbek [user:adedalic,2019-10-23] Dalabaev, Vladimir [user:Vovuh,2019-10-23] Petrov, Ivan [user:BledDest,2019-10-23] Androsov, Maksim [user:Ne0n25,2019-10-23] Mescheryakov and me. Also huge thanks to Mike [user:MikeMirzayanov,2019-10-23] Mirzayanov for great systems Polygon and Codeforces.↵

Good luck to all the participants!↵

Our friends at Harbour.Space also have a message for you:↵

![ ](/predownloaded/35/b6/35b6efd03bbd45a08d3077c0d5513a46fdbcffc2.png)↵

_Hello Codeforces,_ ↵

_We would like to invite all of you to **Mike Mirzayanov's course Advanced Algorithms and Data Structures**, which will take place in Barcelona, from the **6th to 24th of January, 2020**._ ↵

_The course will consist of three weeks of training, 5 training days each week. The program includes daily lectures and practical exercises. It will be quite educational, insightful and entertaining!_↵

_And you will have the opportunity to meet and talk with Mike, who will be happy to share his knowledge and stories about the history of Codeforces._ ↵

_We are happy to offer a special price of **1,000 EUR*** for all Codeforces users._ ↵

_Register on the page below and we will contact you for the next steps. Hurry up! **Only 10 spots available**._↵

_* The cost does not include travel or accommodation._↵

<center style="margin:2.5em;">↵
<a href="https://in.harbour.space/data-science/advanced-algorithms-and-data-structures-mikhail-mirzayanov-2020/?utm_source=codeforces&utm_medium=partners" style="text-decoration:none; font-size:18px; background-color:#523996; color:white; font-weight:bold; padding:0.5em 1em;">REGISTER HERE&rarr;</a>↵
</center> ↵

_We would also like to recommend you an article published on our blog last week about the [5 reasons why traditional universities can’t keep up with humanity](https://harbour.space/about/five-reasons-traditional-education-is-not-keeping-up-with-humanity?utm_source=codeforces&utm_medium=partners)._ ↵

**UPD: The start of the round is postponed by 30 minutes.**


Congratulations to the winners:↵
<table class='bordertable'>↵
<tbody>↵
<tr>↵
<th>Rank</th>↵
<th>Competitor</th>↵
<th>Problems Solved</th>↵
<th>Penalty</th>↵
</tr>↵
<tr>↵
<td>1</td>↵
<td>[user:neal, 2019-10-24]</td>↵
<td>7</td>↵
<td>199</td>↵
</tr>↵
<tr>↵
<td>2</td>↵
<td>[user:Anadi, 2019-10-24]</td>↵
<td>7</td>↵
<td>205</td>↵
</tr>↵
<tr>↵
<td>3</td>↵
<td>[user:risujiroh, 2019-10-24]</td>↵
<td>7</td>↵
<td>208</td>↵
</tr>↵
<tr>↵
<td>4</td>↵
<td>[user:imeimi, 2019-10-24]</td>↵
<td>7</td>↵
<td>229</td>↵
</tr>↵
<tr>↵
<td>5</td>↵
<td>[user:jiangly, 2019-10-24]</td>↵
<td>7</td>↵
<td>273</td>↵
</tr>↵
</tbody>↵
</table>↵

96 successful hacks and 196 unsuccessful hacks were made in total!↵

And finally people who were the first to solve each problem:↵
<table class='bordertable'>↵
<tbody>↵
<tr>↵
<th>Problem</th>↵
<th>Competitor</th>↵
<th>Penalty</th>↵
</tr>↵
<tr>↵
<td>A</td>↵
<td>[user:cxk0707, 2019-10-24]</td>↵
<td>0:02</td>↵
</tr>↵
<tr>↵
<td>B</td>↵
<td>[user:wangziji, 2019-10-24]</td>↵
<td>0:05</td>↵
</tr>↵
<tr>↵
<td>C</td>↵
<td>[user:ZwariowanyMarcin, 2019-10-24]</td>↵
<td>0:06</td>↵
</tr>↵
<tr>↵
<td>D</td>↵
<td>[user:guyan, 2019-10-24]</td>↵
<td>0:16</td>↵
</tr>↵
<tr>↵
<td>E1</td>↵
<td>[user:TwentyOneHundredOrBust, 2019-10-24]</td>↵
<td>0:15</td>↵
</tr>↵
<tr>↵
<td>E2</td>↵
<td>[user:TwentyOneHundredOrBust, 2019-10-24]</td>↵
<td>0:14</td>↵
</tr>↵
<tr>↵
<td>F</td>↵
<td>[user:Radewoosh, 2019-10-24]</td>↵
<td>0:19</td>↵
</tr>↵
</tbody>↵
</table>

History

 
 
 
 
Revisions
 
 
  Rev. Lang. By When Δ Comment
en5 English pikmike 2019-10-25 20:01:00 72
ru7 Russian pikmike 2019-10-25 20:00:39 74
en4 English pikmike 2019-10-25 19:38:59 1669
ru6 Russian pikmike 2019-10-25 19:38:08 1649
en3 English pikmike 2019-10-24 17:16:20 63
ru5 Russian pikmike 2019-10-24 17:15:50 49
ru4 Russian Una_Shem 2019-10-23 21:49:51 3 Мелкая правка: 'n\n_Привет Codeforces,_ \n\n_Мы ' -> 'n\n_Привет, Codeforces!_ \n\n_Мы '
ru3 Russian Una_Shem 2019-10-23 21:48:56 1612
ru2 Russian Una_Shem 2019-10-23 20:00:17 0 (опубликовано)
en2 English Una_Shem 2019-10-23 19:59:04 1623 (published)
en1 English pikmike 2019-10-23 14:57:52 1280 Initial revision for English translation (saved to drafts)
ru1 Russian pikmike 2019-10-23 14:57:00 1397 Первая редакция (сохранено в черновиках)