alex256's blog

By alex256, history, 6 weeks ago, translation, In English,

This is an editorial for the problems of the today's contest. I tried my best to describe the solutions for the problems as detailed as possible, but if something is not understandable for you, you can write in comments! :)

785A - Anton and Polyhedrons

Hint
Tutorial
C++ code
Java code
Python code

785B - Anton and Classes

Hint
Tutorial
C++ code
Java code
Python code

785C - Anton and Fairy Tale

This problem had weak pretests. It was made intentionally to cause more hacks. And I have warned you about it in the announcement :)

Hint
Tutorial
C++ code
Java code
Python code

785D - Anton and School - 2

Hint
Tutorial
C++ code
Java code

785E - Anton and Permutation

I'm sorry that this problem was not original. I will try my best to prevent this from happening again.

If you have TL or ML in this problem, don't think that the time/memory limits are too strict. The model solution works in 1.2 seconds and consumes 9 MB memory.

Hint
Tutorial
C++ code
Java code

Alternative solution from Vladik:

C++ code

Alternative solution from netman:

Java code

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By alex256, history, 6 weeks ago, translation, In English,

Hello, Codeforces!

Tomorrow, in March 15, 2017 at 18:05 MSK a regular rated Codeforces round for participants from the second division will take place. As usual, participants from the first division can take part out of competition. It's my second contest and I hope you'll like it more than my previous one.

As usual, there will be five problems on the contest and two hours to solve them. I advice you to read all the problems' statements attentively. Also check all your solutions for correctness even if they passed all the pretests. Verdict Pretests passed doesn't mean that the solution is completely correct! I wish you to enjoy the contest and learn something new solving the problems.

Like in the last time, the problems will be about Anton and his friends.

Great thanks to Alexey Vistyazh (netman) for help in preparing the contest, Vladislav Vishnevsky (Vladik) for testing the round, Dmitry Klebanov (dakdima) for reading the statements carefully, and of course, Mike Mirzayanov (MikeMirzayanov) for the great platforms Codeforces and Polygon.

Scoring distribution is 500 — 1000 — 1500 — 2250 — 2500.

UPD. The contest is over, system testing has already started, the editorial will appear soon.

UPD2. Editorial has arrived.

UPD3. Congratulations to the winners of the contest!

Div. 1

  1. uwi
  2. rajat1603
  3. SaSa
  4. mr.banana
  5. Kaban-5

Div. 2

  1. liu_cheng_ao
  2. Gauss
  3. binsjl
  4. hotwater
  5. mister_dudec

Thanks everyone for participating :)

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By alex256, 7 weeks ago, translation, In English,

Good afternoon! Today I watched submissions from old contests and found a bug on Codeforces: when you try to see a hacked submission, you'll get an error.

24292787

22241174

22235511

To see the error, you must be logged in on the site. If you are not logged in, the error doesn't appear.

Bugs

In connection with this, I have a question: is there a bugtracker on Codeforces? If there is a bugtracker, it'd be good to give a link to it where anyone can see it. So, bugs that are not fixed, for example, like this or this won't get lost.

UPD: It seems that the bug is fixed.

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By alex256, history, 5 months ago, translation, In English,

Tutorial for the tasks of the contest. If something isn't clear, you can write in comments :)

Tutorial is loading...
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By alex256, history, 5 months ago, translation, In English,

Hello, Codeforces!

Tomorrow, in November 15, 2016 at 19:35 MSK a regular Codeforces round for participants in the second division will be held. As usual, participants from the first division can take part out of competition.

I (alex256) am the author of the contest. It's my first round and I hope it won't be the last. Great thanks to Gleb Evstropov (GlebsHP) for help in preparing the contest, Andrey Kalendarov (Andreikkaa) for testing the round and Mike Mirzayanov (MikeMirzayanov) for the great platforms Codeforces and Polygon.

As usual, the participants will be given 6 problems and two hours to solve them. I recommend to read ALL the problems. I wish everyone many Accepted and, of course, enjoy solving the problems.

The problems will be about my younger brother Anton. I hope you'll like them :)

The round is rated.

UPD: Though, the round won't be completely usual and there will be 6 problems.

UPD2: The scoring is 500-750-1250-1500-2000-2750.

UPD3: Tutorial is available now.

UPD4: Contest is over, congrats to winners :)

Div. 2

  1. Xilya

  2. CisnijAsdPawel

  3. VemMonstro13

  4. fulvioabrahao

  5. Mehrdad_S

Div. 1

  1. sugim48

  2. uwi

  3. khadaev

  4. HellKitsune

  5. Um_nik

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