JuanMata's blog

By JuanMata, 9 years ago, In English

I guess most of you CF regulars will remember a few problems about two characters named Dima and Inna (and their love for each other). I liked most of their problems, and I'm sure I'm not alone.

Now there is some great news — these two awesome people who have kept us entertained with their interesting problems (all the way back from Round #208) have decided to get married! :)

Dima has helped set a lot of problems on CodeChef (also involving the same characters?), and now the CodeChef team has honored him by sending their good wishes to the newlywed couple.

Congratulations to both of you! And please continue to keep the interesting problems coming! :)

EDIT: Below is a photo of Dima (Berezin), Inna, and Sereja.

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By JuanMata, 9 years ago, In English

The 2014 Google Code Jam World Finals will be starting in about twenty minutes from now in Los Angeles.
The winner will receive $15,000 and automatic qualification for the 2015 Code Jam finals.

Here is the contest dashboard. We can see the live scoreboard once the contest starts.
Also, interested people can watch the the live stream on YouTube here.

Wish all the participants good luck! May the best man (or woman) win! :)

Feel free to post your predictions about the contest as comments. Let's see who is able to get closest to the actual outcome! ;)

UPD: Contest has started, and Egor currently leads the scoreboard having solved problem A in less than 8 minutes!

UPD: A little more than one hour into the contest. A lot of coders have solved problem B, but kcm1700 is in the lead after solving problem C. tourist hasn't solved these two yet, but he currently occupies 5th place after solving D-small and E-small.

UPD: Two hours into the contest now. hos.lyric has stayed true to his principle of starting with the harder problems; he has solved D-small, E-small, and F-small, and he currently occupies 7th place. There's now an interesting battle between Egor and eatmore at the top of the scoreboard (Egor currently leads by 4 points).

UPD: Three hours down, just one to go! tourist currently tops the scoreboard, but eatmore has the same points as him, and is only two minutes (on penalty) behind him! This battle looks like it will entertain us all the way until the final minute! al13n and Egor, in 3rd and 4th place respectively, are also equal on points, but al13n is about five minutes (again on penalty) ahead!

UPD: 45 minutes remaining. As eatmore's E-large has expired the time limit, it looks like tourist is heading for victory. But wait, hos.lyric has suddenly jumped into 3rd place; now if he solves any of D-large, E-large, or F-large, he will go to the top of the scoreboard!

UPD: 30 minutes remaining. The only change is that vepifanov has jumped into 3rd place by solving D-large. Still the top two or hos.lyric look most likely to win it all.

UPD: 20 minutes remaining. dzhulgakov has submitted B-large to take the 4th place and sevenkplus has submitted C-large to take the 5th place. 2nd to 5th positions all have 101 points. But the big news is that tourist has made a submission on E-large and now leads the scoreboard by a commanding 35-point margin!

UPD: 10 minutes remaining. eatmore has solved F-small and probably consolidated 2nd place. But the judges say that this solution could possibly work on F-large, so let's wait to see if he submits it there as well! Now I think it's only between tourist and eatmore!

UPD: 5 minutes remaining. eatmore has submitted F-large and has taken the lead over tourist! But wait, ivan.metelsky has suddenly submitted both F-small and F-large to take the second place! This means that tourist is in third now.

UPD: CONTEST HAS FINISHED! The current positions (assuming everybody passes system tests on all large inputs) are:

  1. eatmore — 165 points
  2. ivan.metelsky — 137 points
  3. tourist — 136 points
  4. vepifanov — 101 points
  5. dzhulgakov — 101 points
  6. sevenkplus — 101 points
  7. Romka — 101 points
  8. iwiwi — 101 points

UPD: The final results are announced! Many congratulations to tourist for winning the big prize! :)

UPD: The final scoreboard is now available here. The top 7 are:

  1. tourist — 136 points
  2. eatmore — 123 points (failed F-large)
  3. sevenkplus — 101 points
  4. ivan.metelsky — 95 points (failed F-large)
  5. al13n — 89 points
  6. Egor — 89 points
  7. kcm1700 — 89 points

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By JuanMata, 9 years ago, In English

A few hours ago, I noticed a very long thread of spam comments on many different posts on CF, but most of them appear to have disappeared!

However, I was able to catch most of these comments (a "subarray" of the Recent actions page, if you like) in a PDF document. You can follow the links to various pages on the document by clicking on them (just like if you were reading the comments on CF).

I hope a few other users also noticed these comments. I'm sure all of you were very frustrated that there were so many of them. Surely we need to do something to make CF better.

Also, there have been many more spam posts/comments from these three users (delairer, contest1234, and majid1234) in the past few weeks. I think they should be banned from CF, or atleast prevented from writing any more posts/comments in future (if this is possible).

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By JuanMata, 9 years ago, In English

Hello everyone!

Codeforces Round #258 (Div. 2) will take place on July 24, 19:30 MSK. Traditionally, Div. 1 users can take part out of the competition.

The round was prepared by PraveenDhinwa and me (JuanMata). This is our second Codeforces round, and hopefully not our last.

We have tried our best to make the problem statements as clear and interesting as possible. We hope that everyone will enjoy the round. :)

Special thanks to MikeMirzayanov for creating the wonderful Polygon and Codeforces platforms, Gerald for his extensive help in problem verification and testing, and Delinur for translation of problem statements into Russian. Without their help the contest would never have seen the day.

We wish all the participants good luck and high rating. :)

UPD: It is decided to use the dynamic scoring system.

UPD: Contest is finished. You can find the editorial here. :)

UPD: Congratulations to the winners. Here are the top 8 (the only ones to solve all the problems):

  1. skank
  2. western_theory
  3. jurbhm538
  4. chenrui9551
  5. zhouhebin
  6. MaxKU
  7. jmas2711
  8. hzwer

UPD: Wonderful statistics by DmitriyH can be found here. :)

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By JuanMata, 10 years ago, In English

Tomorrow will take place the Qualification Round of Google Code Jam 2014.
Contest will start 14 hours from now. Note that the contest duration has been extended by 2 hours, so now it will be 27 hours long! :)
Registration for the round has already started, and will be open until end of contest.

Wish all participants good luck in advancing to Round 1. You must score atleast 25 points to advance.

We can discuss the problems here after contest!

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By JuanMata, 10 years ago, In English

Today will take place TopCoder SRM 616. Wish all participants good luck and high rating!
Contest starts exactly 65 minutes from now, so register yourselves on the arena before the next hour in order to participate.

Let's discuss the problems here after the contest.

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By JuanMata, 10 years ago, In English

Today I saw a thread where users were discussing that we can have these type of contests more frequently than once a year. I too share this opinion, and I have an idea for this.

Let Codeforces have two different ratings (like TopCoder has Algorithm and Marathon ratings separately).

  • The first (already existing Algorithm rating) will be for regular contests. This will be the "actual" rating, and CF already has this.
  • The second one (we can call it Fool's Gold or some funny name :D) will be for contests like the April Fools contest, which can be held probably once in a month! Ideally it could be 1st of every month, but the exact schedule can be decided by admins.

I agree that organizing this type of contests monthly will be time-consuming for the setters, so maybe we can have fewer problems (less than the 9 we had in this month's contest), ideally about 4-5 problems per contest. Naturally, this would mean reducing the contest duration from 120 minutes to about 90 minutes.

Please comment below if u have any suggestions.

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