Shafaet's blog

HackerRank HourRank — 11
By Shafaet, history, 8 years ago, In English

Hello everyone!

I am glad to invite you to the 11th edition of HourRank. The contest starts on August 2nd 16:30 UTC (View local time).

HourRank is a super short one hour long algorithmic contest. This time we will have 3 challenges, created by me, harshil and forthright48. As always, thanks to wanbo for testing the challenges and thanks to pkacprzak for helping with editorials.

There are subtasks in each of the problems, so I strongly encourage you to read all the problems.

Participants are ranked by score. If two participants have the same score, the one who reached the score first, wins.

Top-10 contestants will get a HackerRank Tshirt.

In the last round no one was able to get perfect score (though all the problems were solved). Let's see what happens in this round!

Update: scoring 30-50-75

The contest ended. The editorials are now open. Congrats to the winners:

anta

Zlobober

el_sanchez

yosupo

I_love_Tanya_Romanova

Only top 4 got the perfect score. Congrats to all.

I hope you liked the round, please share your feedbacks.

Happy Coding!

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8 years ago, # |
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I wonder why no info about the t-shirts is written on the website...

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    8 years ago, # ^ |
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    We forgot to mention it. I added the info now, thanks.

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8 years ago, # |
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There are subtasks, that's cool! Do we get the score of a subtask when we pass a group of tests, or is it some points for every passed test case? I really hope it's for groups...

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    8 years ago, # ^ |
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    That is not groups for sure. But in many contests last time, there is the same number of testcases as number of more important subtasks ( normally some tasks can not have it + nobody can not mention each subtask).

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      8 years ago, # ^ |
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      But I think to do fair "get the score of a subtask when we pass a group of tests for that subtask" is very important issue.

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        8 years ago, # ^ |
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        I agree with you. But we don't have such system at this moment. We tried to keep it as fair as possible.

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8 years ago, # |
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A link to a contest would be convenient (and here's the link). Hope to see interesting problems.

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    8 years ago, # ^ |
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    Ooops how did I miss it! Added the link now, thanks.

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8 years ago, # |
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Off-topic: will you eventually have moderated comments (not public by default)? Would be so awesome.

Also, is it possible to download codes from the leaderboard?

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    8 years ago, # ^ |
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    You can download from leaderboard now, we unlocked the solutions.

    I hope we will eventually have moderated comments, I know why it's bothering you. But I am not sure when we will have it.

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8 years ago, # |
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Hi everybody!

This was my first time participating in something serious on HR, kind of a new experience for me. Can somebody please point me to the description of what kinds of rounds does HR hold regularly? Or just describe in a few words what are the main type of contests and their approximate difficulty level so that I can track some kinds of them and participate in them regularly?

Nice problems, kudos to authors.

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    8 years ago, # ^ |
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    Glad to know that you liked the round! Let me tell you about the regular rounds.

    • 101 hack — A 2 hour contest with 5 problems, similar to CF div1-div2 combined rounds.
    • HourRank — A 1 hour contest with 3 or 4 problems.
    • Week of code — A 7 day contest. 1 challenge is revealed per day. It has pre-tests like CF, we run the main testcases after each day ends.
    • World Codesprint — 24 hour contests with 7 or 8 problems. It have big prizes and sponsors.
    • Infinitum — Once in 3 months we arrange a math-only contest.

    You can see some of the old contests here!

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      8 years ago, # ^ |
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      Thanks, I've starred you comment in order to have it in bookmarks.

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    8 years ago, # ^ |
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    Something to add to comment by Shafaet:

    HourRank — full feedback, contestants are ranked by the time they used to reach their score (like in GCJ), no penalties.

    101Hack — full feedback, no penalties, contestants ranked by sum of times they needed to reach their score on each problem — like in ICPC.

    Week of Code — feedback on pretests only when you submit, system testing at the end of the day; contestants ranked by sum of times (like in ICPC), time is counted from the moment you opened the problem (therefore you'll see folks solving problems in 10 seconds at the top of the standings during a contest :) ), but maximum possible score for a problem decreases each day (so for maximum result you have to solve it within a day from the moment it has been published). No penalties as well, all submissions are being tested — you can make even 100 attempts on a problem and you'll get score equal to the best result at system testing.

    Most of the problems have partial scoring; sometimes 0/1 scoring is used for some of the problems in the contest, while other problems still have partial scoring; in some rare cases naive solutions are scoring 0 but problem formally isn't considered to be a problem with partial scoring (I've seen such situation only once or twice).

    You can figure out approximate difficulty of past contests from standings :) But it varies quite a lot.

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      8 years ago, # ^ |
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      "therefore you'll see folks solving problems in 10 seconds at the top of the standings during a contest"
      What about after the contest? do they get disqualified?

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8 years ago, # |
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I hope one day I will be able to tell my grandchildren about how ratings used to get hours and hours to update for no known reasons on all competition websites...

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    8 years ago, # ^ |
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    Rating is being updated now, will be finished soon. The reason for delay is we run a plagiarism checker before updating the rating to detect cheats.

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8 years ago, # |
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It was a great contest, it is an excellent challenge for be faster!!

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