kostka's blog

By kostka, 3 weeks ago, In English,

Just in a month from today, IOI in Iran will start.

Below you can find the complete list of participants (based on registration and data provided by Codeforces community): http://weaselcrow.com/pro/cf/ioi2017/

Some random facts:

  • 326 students from 84 countries will participate (this will be a new record, the previous record was at IOI 2015 in Kazakhstan — 322 contestants from 83 countries)
  • El Salvador, Iceland, Morocco, and Palestine will send their contestants for the very first time, welcome to IOI!
  • 114 (almost 35%) participants were already in Russia, including golden medalists: reyna, yutaka1999, pacu, natsukagami, also Cyprus and Bangladesh will have exactly same team, as in previous year.

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By kostka, 3 months ago, In English,

Maintaining tradition from last year and the year before last I want to start a list of participants of the International Olympiad in Informatics 2017.

This year IOI will be held in Tehran, Iran between 28th July and 4th August.

Official website: http://ioi2017.org/

Facebook page: ioi2017.org


Update:

Check out the new version of this list with sorting and CF rating (updated by CF API):

http://weaselcrow.com/pro/cf/ioi2017/


Feel free to add (confirmed!) participants from your country here: https://goo.gl/forms/4BskHKHmZ70Tdck22 (preferred way) or below, in comments.

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By kostka, 7 months ago, In English,

This topic is probably as old as programming itself, but maybe someone can help me.

I had an opportunity to organize several camps for some pupils (age 14-16). They were pretty good in mathematics and puzzles in general. My job there was to show them why programming (and algorithms) is also pretty decent.

I show them some problems, teach them basic programming skills, but after several years I noticed that the most important thing in teaching such things is showing them why programming is important and why should they learn this. I should sell them not knowledge, but attitude during this week.

Do you have any idea how to convince younger generations why they should start programming? Why did you start? What is convincing you to still solve algorithmic problems?

Happy New Year and thanks in advance for your responses and ideas :)

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By kostka, 15 months ago, In English,

In next week, Baltic Olympiad in Informatics 2016 will be held in Helsinki, Finland.

The Baltic Olympiad in Informatics (BOI) is a programming contest for secondary school students. It started in 1995 with only 3 participating countries and grew substantially over the years. Now BOI encompasses about 60 participants from 9 countries situated around the Baltic Sea. Each country is invited to send up to 6 participants to the Olympiad, and the host country usually sends two teams. (from BOI 2015 webpage).

The contest website: https://www.cs.helsinki.fi/group/boi2016 and facebook page: https://web.facebook.com/boi2016/

Even Codeforces Round #352 is taken into account in schedule!

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By kostka, 16 months ago, In English,

Did you notice that in the top navbar something is missing?

Old navbar:

Current navbar:

I wonder if I miss something about these links being deleted, but I hope they will come back (many questions like this can be answered directly by reading HELP page, am I right?). Moreover: these pages still work.

TLDR: Please give back help and testlib to navbar!

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By kostka, 16 months ago, In English,

Welcome back to Hack me! blog!

You asked for it, and you have it. After over one year I am back with short description of the best hackers and the most common hacks in Codeforces Round. The formula is quite new and poorer than before, I should say. I left only the most important messages.

If you are not familliar with the series, you may check my first post about it or all posts.

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By kostka, 19 months ago, In English,

Hey there, I couldn't sleep, so I spend almost an hour to play with some Python and answering some questions about "who was... in 2015 on Codeforces" (also checking if I still remember anything :)). So — have you ever wondered who was the best in this year on Codeforces? I will try to answer to your (and mostly mine) questions. Here is the first part (and maybe the last :)) of this year review.

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By kostka, 2 years ago, In English,

Hey there.

There is a contest in Poland called Deadline24. It is 24 hours long programming marathon where you are programming bots for games.

We are looking (with skedar) for a third party member. We can offer:

  • noble company
  • almost certainty to advance to the finals (we are in the finals since we started participating) and the finals includes:
  • trip to Silesia in Poland, to the old carbon mine, (unfortunately you will have to pay for your travel yourself),
  • possibility to die from overeating (the organizers provide food for 24 hours: pizzas, snacks, etc.),
  • flashdisk (lol :))
  • really nice diploma and cerificate (in English, of course)

The tasks are in English.

Scheldule:

  • Registration: up until February 26, 2015
  • Qualifying round: March 1, 2015
  • Finals (on site!): April 7-8, 2015

What we want is someone who can write a program (not necessarly fast and good program, but it will be nice :)). If you took part in such contests, that will be really big point. Please write a message to me if you are interested and tell us something about yourself. I will try to answer to all your questions.

Maybe you have a team and you want to participate? Check their website (link above).

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By kostka, 2 years ago, In English,

Hey there.

I haven't posted any post in this year and some people asked what will happen with my posts about hacks. The answer is "they will come" in indefinite time. I am unfortunately quite busy with other stuff (I didn't even had enough time to take part in any round this year :(). The statistics are ready, but I don't have enough time to look at hacks and describe them. For those, who are waiting, I am really sorry.

I also want to upgrade my scripts — I took all of your suggestions and I am currently thinking how to fulfil all your whims :) For example, I want to keep such ranking as was seen here and update it after every round.

Looking forward to more of your feedback and see you later :)

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By kostka, 3 years ago, In English,

Still in buoyant humour after Good Bye 2014? While waiting for the editorial, maybe you would like to know why there were so many hacks in the last round of this year?

As always, please share you thoughts, ideas or maybe hacks :)

Previous posts can be found here.

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By kostka, 3 years ago, In English,

Hey there!

This is the third part of my little summing-up of the ending year. This one is pretty big. I went through all submissions from every contest from this year and created the list of the most hacked problems in this year. Moreover, this list has some other informations like what was the problem with the biggest or the lowest number of accepts to it, what problems had strong and weak pretests and many more...

Check the full list here.

Be careful with some data, because you may not remember the Black Day of Codeforces, when some data was lost and in fact, it appears that there were no participants (and submits) for some round (it apply to most of the contests in February). Also, you may surprised that some hacks are count several times — it is because some people resubmitted their hacked solutions (without success) and I wondered where put such submission. I decided to keep it there (frankly, there were not so many such submissions so it doesn't change a lot).

The previous parts:

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By kostka, 3 years ago, In English,

And statistics from Codeforces Round #284 (Div. 2) (this round should be named after dreamoon).

Previous posts can be found here, including post for div. 1.

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By kostka, 3 years ago, In English,

Let's take a look at Christmas Round (Codeforces Round #284 (Div. 1)).

Because of not-so-good scheduling, I didn't take part in it (neither any of my friends did). In Poland, it is a nice time to spend time with family, not like this. If you are interested how Christmas look like in Poland, check out polishchristmasguide.com.

Ok, enough complaining, let's look at the hacks.

Previous posts can be found here, including post for div. 2.

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By kostka, 3 years ago, In English,

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). Now we will show all most accurate hackers. We will count the accuracy as the:

Because there were a lot of flawless hackers, below we show only hackers with at least 10 successful hacks — still there were 36 of them!

The full list of hackers' accuracy can be found here.

Also, below this table there is updated list of best hackers by summarized points, also the full list was updated here.

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By kostka, 3 years ago, In English,

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 (so far), the full list can be found here.

Update: After last round, the ranking was updated.

The last round was decisive: mosiomohsen made 5 successful hacks and 1 unsuccessful and with 450 points, he managed to surpass anta. Congratulations!

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By kostka, 3 years ago, In English,

And Codeforces Round #283 (Div. 1).

It wasn't very good round for hackers (especially because of strong pretests), but still — let's take a quick look. (Hacks description will be added later, maybe tomorrow?)

Previous posts can be found here, including div. 2.

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By kostka, 3 years ago, In English,

Hey there! Here are the hacking statistics from Codeforces Round #283 (Div. 2).

It wasn't very good round for hackers (especially because of strong pretests), but still — let's take a quick look. (Hacks description will be added later, sorry).

Previous posts can be found here, including div. 1.

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By kostka, 3 years ago, In English,

Aren't you tired after Codeforces Round #282 (Div. 1)?

Did you know...

that when you will be on the list of "best hackers" of the round the row with your handle will be highlighted (if you will be logged in)?

Other posts can be found here, including div2.

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By kostka, 3 years ago, In English,

Quite delayed, but here we have stats about hacks in Codeforces Round #282 (Div. 2).

Previous posts can be found here, including div1.

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By kostka, 3 years ago, In English,

While waiting for API to update, (it has been updated already) let's look at hacks in Codeforces Round #281 (Div. 2). That was really good round (even I had some hacks :)).

Previous posts can be found here.

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By kostka, 3 years ago, In English,

Brief stats about some past contest — Codeforces Round #280 (Div. 2).

Previous posts can be found here.

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By kostka, 3 years ago, In English,

Hello and welcome in Codeforces Round #279 (Div. 2) — description of hacks.

Previous posts can be found here.

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By kostka, 3 years ago, In English,

Waiting for next round, let's take some time and look at hacks in Codeforces Round #278 (Div. 1). That was really good round for hackers :)

Previous posts (including post for Div. 2.) can be found here.

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By kostka, 3 years ago, In English,

Welcome in hacks' statistics in Codeforces Round #278 (Div. 2). That was really nice round for hackers! Many possibilities, many hacks, let's have a look!

Post for Div. 1. contest will be added later (there are pretty many hacks to parse :)) is here.

Previous posts can be found here.

Your comments are always welcome.

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By kostka, 3 years ago, In English,

Welcome after the long break in Hack me! (Codeforces Round #277.5 (Div. 2)).

Previous posts can be found here.

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