rng_58's blog

By rng_58, history, 8 hours ago, In English,

AtCoder Grand Contest 009 will be held on Sunday (time). The writer is DEGwer.

Contest Link

Contest Announcement

The point values are 300 — 800 — 1100 — 1400 — 1600.

Note that the duration and the number of tasks is a bit unusual: 5 tasks in 2 hours.

Let's discuss problems after the contest.

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By rng_58, history, 3 weeks ago, In English,
 
 
 
 
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By rng_58, history, 3 weeks ago, In English,

Who is this?

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By rng_58, history, 4 weeks ago, In English,

Sorry for late announcement, I completely forgot it.

AtCoder Grand Contest 008 will start soon! https://agc008.contest.atcoder.jp/

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By rng_58, history, 4 weeks ago, In English,

Hello.

I'm planning to participate in a contest tonight. This is a team contest — and unlike ICPC, there is no limit to the number of computers. So, essentially this is an individual contest, and the score of a team is defined as the union of problems solved by the team members. I'm looking for my teammates in this contest.

The problem statements are provided only in Japanese. However, don't be afraid. If you become my teammate, I will describe the problems in English. (I may also solve a few problems myself, but I'm not sure).

The contest will start at https://www.timeanddate.com/worldclock/fixedtime.html?iso=20161224T22&p1=248, and the duration of the contest is 4 hours. If you are interested in it, please reply this post until 30 minutes before the contest (that is 80 minutes from now).

This is a non-serious contest, and I won't care the rank too much — the main purpose of this contest is to have fun. Some problems may be unusual.

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By rng_58, history, 2 months ago, In English,

The onsite events of CODE FESTIVAL 2016 will start soon. I'll keep posting commentaries here. All times written here are Japanese Standard Time, which is UTC+9 or Moscow Time + 6.

[25th, Friday 21:25]

As the name of the contest may suggest, there are lots of events, including five contests:

  • CODE FESTIVAL 2016 Final

  • CODE FESTIVAL 2016 Exhibition

  • CODE FESTIVAL 2016 Elimination Tournament (3 rounds)

  • CODE FESTIVAL 2016 Relay

  • CODE FESTIVAL 2016 Grand Final

Some events are even overlapping so you have to choose one of them.

For those who can't attend the onsite events, there will be open contests. Please check the details at https://atcoder.jp/post/58 (here times are also written in JST). The Finals will start at Saturday 12:30, UTC+9.

[26th, Saturday 16:19]

Final Standings: https://cf16-final.contest.atcoder.jp/standings

The winner of Final is tourist. Congratulations!

The winner of Grand Final is W4yneb0t. Congratulations!

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By rng_58, history, 2 months ago, In English,

Semifinal 1 will start in 43 minutes.

Broadcast: https://www.twitch.tv/topcoder_official

TCO Blog (I'm the blog writer): http://tco16.topcoder.com/blog/

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By rng_58, history, 2 months ago, In English,

AtCoder Grand Contest 007 will be held on Saturday (time). The writer is doreamon.

Contest Link

Contest Announcement

The point values are 200 — 400 — 1000 — 1200 (600) — 1400 — 1500.

Let's discuss problems after the contest.

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By rng_58, history, 3 months ago, In English,

AtCoder Grand Contest 006 will be held on Saturday (time). The writer is sugim48.

Note that this time the contest duration is 130 minutes (20 minutes longer than usual).

Contest Link

Contest Announcement

The point values are 200 — 400 — 800 — 1300 — 1500 — 1700.

Let's discuss problems after the contest.

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By rng_58, history, 3 months ago, In English,

CODE FESTIVAL 2016 Qualification Round C will be held on Sunday Monday (time). The writer is sigma425.

Contest Link

Contest Announcement

This is one of the three qualification rounds of CODE FESTIVAL. Top 5 foreign students of this round will qualify. If you are eligible for the onsite contest, please don't forget to fill the form at https://krs.bz/rhd-itm/m/code_fes_2016. Please check the detail of the tournament at http://codeforces.com/blog/entry/46647.

The contest duration is 2 hours, and there will be 5 problems. The first 4 problems are mainly used for choosing domestic students and much easier than other tournament competitions. However, we added one more problem and we hope this is interesting enough for choosing top 5 qualifiers. (Anyway, most probably the qualifiers will be determined by the speed of solving all problems). Note that there is no time penalty for incorrect submissions. The time penalty is MAX, not SUM.

The point values are 100 — 200 — 400 — 800 — 1200. If you are unfamiliar with AtCoder System, 2X-point problem in AtCoder is as hard as TopCoder's d1 X-point problem.

Let's discuss problems after the contest.

UPD: Fixed the date.

UPD: The top 5 were jcvb, w4yneb0t, AlexDmitriev, xyz111, and xyz2606. Congratulations!

UPD: Since wwwwodddd turned out to be a cheater, this account was excluded from the contest and banned from AtCoder. The qualifiers and the ratings were recomputed.

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By rng_58, history, 3 months ago, In English,

CODE FESTIVAL 2016 Qualification Round B will be held on Monday (time). The writer is DEGwer.

Contest Link

Contest Announcement

This is one of the three qualification rounds of CODE FESTIVAL. Top 5 foreign students of this round will qualify. If you are eligible for the onsite contest, please don't forget to fill the form at https://krs.bz/rhd-itm/m/code_fes_2016. Please check the detail of the tournament at http://codeforces.com/blog/entry/46647.

The contest duration is 2 hours, and there will be 5 problems. The first 4 problems are mainly used for choosing domestic students and much easier than other tournament competitions. However, we added one more problem and we hope this is interesting enough for choosing top 5 qualifiers. (Anyway, most probably the qualifiers will be determined by the speed of solving all problems). Note that there is no time penalty for incorrect submissions. The time penalty is MAX, not SUM.

The point values are 100 — 200 — 500 — 700 — 1100. If you are unfamiliar with AtCoder System, 2X-point problem in AtCoder is as hard as TopCoder's d1 X-point problem.

Let's discuss problems after the contest.

UPD: Among the top 5 foreign participants, Arterm has already qualified from round A, and matthew99, Reyna, Tachibana-Kanade are too young. Congratulations to Merkurev, polequoll, fqw, sevenkplus, and Zlobober! Note that this information is unofficial, and it is possible that some of them don't want to participate in finals (or ineligible).

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By rng_58, history, 4 months ago, In English,

Let's discuss problems.

How to solve 8? I have no idea at all and finally decided to believe that we don't need nested addition/subtraction blocks, but it got WA. It seems there are harder cases.

How to solve 12? Essentially it reduces to the following: you are given a circle C and a point P. Find the movement of a point on C whose angular velocity is proportional to the distance from P. Is numerical integration accurate enough?

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By rng_58, history, 4 months ago, In English,

AtCoder Grand Contest 005 will be held on Saturday (time). The writer is yosupo.

Contest Link

Contest Announcement

Let's discuss problems after the contest.

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By rng_58, history, 4 months ago, In English,

CODE FESTIVAL 2016 Qualification Round A will be held on Saturday (time). The writer is sugim48.

Contest Link

Contest Announcement

This is one of the three qualification rounds of CODE FESTIVAL. Top 10 foreign students of this round will qualify. If you are eligible for the onsite contest, please don't forget to fill the form at https://krs.bz/rhd-itm/m/code_fes_2016. Please check the detail of the tournament at http://codeforces.com/blog/entry/46647.

The contest duration is 2 hours, and there will be 5 problems. The first 4 problems are mainly used for choosing domestic students and much easier than other tournament competitions. However, we added one more problem and we hope this is interesting enough for choosing top 10 qualifiers. (Anyway, most probably the qualifiers will be determined by the speed of solving all problems). Note that there is no time penalty for incorrect submissions. The time penalty is MAX, not SUM.

The point values are 100 — 200 — 400 — 800 — 1200. If you are unfamiliar with AtCoder System, 2X-point problem in AtCoder is as hard as TopCoder's d1 X-point problem.

Let's discuss problems after the contest.

UPD: Congratulations to tourist, endagorion, LHiC, Arterm, Kostroma, mmaxio, Um_nik, ainu7, malcolm, FatalEagle! (I don't know who is eligible and this is not the official information, please let me know if some of them won't come.)

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By rng_58, history, 5 months ago, In English,

Note: The contest was moved to Sunday in order to avoid collision with TCO Russia.

AtCoder Grand Contest 004 will be held on Sunday (time). The writer is sugim48.

Contest Link

Contest Announcement

Let's discuss problems after the contest.

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By rng_58, history, 5 months ago, In English,

AtCoder Grand Contest 003 will be held on Sunday (time). The writer is DEGwer.

Contest Link

Contest Announcement

Let's discuss problems after the contest.

Also, we've just announced Code Festival 2016!

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By rng_58, history, 5 months ago, In English,

We announce a new international onsite competition: Code Festival 2016. The contests will be held on AtCoder.

The top 20 foreign (non-Japanese) university students are invited to the Finals in Japan. (Even if you are not a student, you can participate in qualification rounds and parallel rounds of onsite contests. All of these contests are rated.)

The flight tickets and hotels for finalists are paid by organizers.

There will be three qualification rounds. Top 10 foreign students from round A and top 5 each from round B and C will qualify for the onsite contest.

Also, there will be many interesting events during the onsite competition.

More detailed information can be found at the official website.

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By rng_58, history, 6 months ago, In English,

All testcases of atcoder problems will be posted here: https://www.dropbox.com/sh/arnpe0ef5wds8cv/AAAk_SECQ2Nc6SVGii3rHX6Fa?dl=0

If you are interested in the rating system, please check rating.pdf at https://www.dropbox.com/sh/zpgcogxmmu84rr8/AADcw6o7M9tJFDgtpqEQQ46Ua?dl=0

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By rng_58, history, 6 months ago, In English,

AtCoder Grand Contest 002 will be held on Sunday (time). The writer is sugim48.

Contest Link

Contest Announcement

Let's discuss problems after the contest.

UPD: Thank you for participation. Editorial (English at the bottom)

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By rng_58, history, 6 months ago, In English,

AtCoder Grand Contest 001 will start soon (time).

Note that you need to click the blue button here to register.

Let's discuss problems after the contest.

The contest duration is changed to 110 minutes.

The contest has finished. How was the contest?

Congratulations to cgy4ever for winning!

Editorial: https://agc001.contest.atcoder.jp/data/agc/001/editorial.pdf (English is at the bottom)

UPD: The rating is updated.

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By rng_58, history, 6 months ago, In English,

Hello!

We made a new programming contest website called AtCoder. I'm the admin of AtCoder.

The first international contest called AtCoder Grand Contest 001 will be held on this Saturday (Time), and we are planning to hold a lot of contests regularly. This time the problems were written by snuke. We invite you to participate in our contests!

See AtCoder's Website for detailed information.

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By rng_58, history, 7 months ago, In English,
CF Handle Country
1. xyz111China
2. kevinsogoPhilippines
3. touristBelarus
4. TooDifficuItChina
5. ksun48Canada
6. eatmoreRussia
7. yosupoJapan
8. ffaoBrazil
9. simonlindholmSweden
10. marcin_smuPoland
11. s-quarkChina
12. gs12117South Korea
13. mnbvmarPoland
14. xllend3China
15. Savlik5Czech Republic
16. semiexpJapan
17. rng_58Japan
18. jcvbChina
19. andrewztaRussia
20. MerkurevRussia
21. NoreFrance
22. scott_wuUnited States
23. ArtermBelarus
24. wuzhengkaiChina
25. XharkSouth Korea
26. pashkaRussia

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By rng_58, history, 11 months ago, In English,

I was an admin of TopCoder for about 4 years. Recently I came back as a competitor and I participated in four SRMs. Here are my performances:

SRM 681 Hard: CoinFlips

It was an easy DP, but I started to implement something stupid and wasted time. When I finished coding around 5 minutes before the end of the contest, the server was slow and I couldn't compile my solution. Though the match was unrated, I should have solved it earlier.

SRM 682 Hard: TheKFactor

My solution failed because of precision errors (in Linear Programming). I should have used long doubles instead of doubles (and passed in the practice room).

SRM 683 Hard: RandomWalkOnGrid

Failed systest because of two (!) stupid mistakes: incorrect array size and integer overflow.

SRM 684 Hard: Permutant

Missed cases with a.size() == 1. Failed systest again.

It's really important to keep participating in TopCoder matches. Now I can't solve anything!

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By rng_58, history, 12 months ago, In English,
CF Handle Country
1. bmerrySouth Africa
2. PetrRussia
3. TooDifficuItChina
4. rng_58Japan
5. AlexDmitrievRussia
6. Um_nikRussia
7. I_love_Hoang_YenVietnam
8. eatmoreRussia
9. Al.CashUkraine
10. snukeJapan
11. ACRushChina
12. kcm1700South Korea
13. scott_wuUnited States
14. uwiJapan
15. MerkurevRussia
16. doreamonTaiwan
17. simonlindholmSweden
18. kelvinTaiwan
19. KANRussia
20. azukunRussia
21. ZloboberRussia
22. yosupoJapan
23. krismazPoland
24. yeputonsRussia
25. ShikTaiwan

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By rng_58, history, 14 months ago, In English,
 
 
 
 
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