Educational Codeforces Round 92 [Rated for Div. 2]
Difference between en2 and en3, changed 2,510 character(s)
Hello Codeforces!↵

On [contest_time:1389] [contest:1389] 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 **6 or 7 problems** and **2 hours** to solve them.↵
 ↵
The problems were invented and prepared by Roman [user:Roms,2020-07-28] Glazov, Adilbek [user:adedalic,2020-07-28] Dalabaev, Vladimir [user:vovuh,2020-07-28] Petrov, Ivan [user:BledDest,2020-07-28] Androsov, Maksim [user:Ne0n25,2020-07-28] Mescheryakov and me. Also huge thanks to Mike [user:MikeMirzayanov,2020-07-28] Mirzayanov for great systems Polygon and Codeforces.↵

Good luck to all the participants!↵

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

<img alt="Codeforces and Harbour.Space" src="https://codeforces.com/predownloaded/0a/83/0a83c1a2218f17a8d5d26e06275b991ae53230b8.png" style="float:center;height: 350px; margin: 10px; max-width:50%;"/>↵

_Hey Codeforces!_ ↵

_We hope you’ve been doing well these past couples of weeks._↵

_This week, we wanted to share a blog post about two of our students. As you might know, Harbour.Space has a unique approach to education &mdash; besides classwork and exams, we encourage our students to develop their skills with hands-on projects or even create their startups, so that they’re ready for the workforce when they graduate._ ↵

_That’s exactly what Jonathan and Khaled, two of our Data Science students, did._↵

_After working hard on their Machine Learning-based startup, they were selected by the European Organization for Nuclear Research (CERN) for a 5 Week Student Entrepreneurship Programme, and are now preparing to travel to Geneva in October. We summarized the story of how they went from data scientists to startup founders in this article._ ↵

_We hope it inspires you to pursue your passions, and work collaboratively to improve the world for those around you._ ↵

_Good luck on your round, and see you next time!_ ↵

<center style="margin:2.5em;">↵
<a href="https://harbour.space/data-science/articles/from-data-science-to-cern-how-two-students-are-building-their-machine-learning-based-startup?utm_source=codeforces&utm_medium=partners" style="text-decoration:none; font-size:16px; background-color:#523996; color:white; font-weight:bold; padding:0.5em 1em;">Read article&rarr;</a>↵
</center> ↵

<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:Um_nik, 2020-07-29]</td>↵
<td>7</td>↵
<td>245</td>↵
</tr>↵
<tr>↵
<td>2</td>↵
<td>[user:I_love_chickpea, 2020-07-29]</td>↵
<td>7</td>↵
<td>255</td>↵
</tr>↵
<tr>↵
<td>3</td>↵
<td>[user:kefaa2, 2020-07-29]</td>↵
<td>7</td>↵
<td>267</td>↵
</tr>↵
<tr>↵
<td>4</td>↵
<td>[user:Egor, 2020-07-29]</td>↵
<td>7</td>↵
<td>293</td>↵
</tr>↵
<tr>↵
<td>5</td>↵
<td>[user:Farhod_Farmon, 2020-07-29]</td>↵
<td>7</td>↵
<td>364</td>↵
</tr>↵
</tbody>↵
</table>↵


Congratulations to the best hackers:↵
<table class='bordertable'>↵
<tbody>↵
<tr>↵
<th>Rank</th>↵
<th>Competitor</th>↵
<th>Hack Count</th>↵
</tr>↵
<tr>↵
<td>1</td>↵
<td>[user:Joney, 2020-07-29]</td>↵
<td><b><font color="green">20</font></b><b>:<font color="red">-2</font></b></td></td>↵
</tr>↵
<tr>↵
<td>2</td>↵
<td>[user:applese, 2020-07-29]</td>↵
<td><b><font color="green">19</font></b><b>:<font color="red">-1</font></b></td></td>↵
</tr>↵
<tr>↵
<td>3</td>↵
<td>[user:FelixArg, 2020-07-29]</td>↵
<td><b><font color="green">7</font></b><b>:<font color="red">-2</font></b></td></td>↵
</tr>↵
<tr>↵
<td>4</td>↵
<td>[user:liouzhou_101, 2020-07-29]</td>↵
<td><b><font color="green">10</font></b><b>:<font color="red">-10</font></b></td></td>↵
</tr>↵
</tbody>↵
</table>↵
116 successful hacks and 492 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:noimi, 2020-07-29]</td>↵
<td>0:00</td>↵
</tr>↵
<tr>↵
<td>B</td>↵
<td>[user:noimi, 2020-07-29]</td>↵
<td>0:05</td>↵
</tr>↵
<tr>↵
<td>C</td>↵
<td>[user:Ari, 2020-07-29]</td>↵
<td>0:04</td>↵
</tr>↵
<tr>↵
<td>D</td>↵
<td>[user:HanaYukii, 2020-07-29]</td>↵
<td>0:17</td>↵
</tr>↵
<tr>↵
<td>E</td>↵
<td>[user:kefaa2, 2020-07-29]</td>↵
<td>0:22</td>↵
</tr>↵
<tr>↵
<td>F</td>↵
<td>[user:nitixkrai, 2020-07-29]</td>↵
<td>0:23</td>↵
</tr>↵
<tr>↵
<td>G</td>↵
<td>[user:MyK_00L, 2020-07-29]</td>↵
<td>1:05</td>↵
</tr>↵
</tbody>↵
</table>↵



**UPD:** [Editorial is out](https://codeforces.com/blog/entry/80809)

History

 
 
 
 
Revisions
 
 
  Rev. Lang. By When Δ Comment
en3 English awoo 2020-07-30 15:09:46 2510
ru4 Russian awoo 2020-07-30 15:08:58 2519
ru3 Russian Una_Shem 2020-07-28 21:11:15 1701
ru2 Russian Una_Shem 2020-07-28 17:13:54 0 (опубликовано)
en2 English Una_Shem 2020-07-28 17:13:22 1687 (published)
en1 English awoo 2020-07-28 16:59:18 1285 Initial revision for English translation (saved to drafts)
ru1 Russian awoo 2020-07-28 16:58:27 1401 Первая редакция (сохранено в черновиках)