Arpa's blog

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

Hello everyone!

Another long and exciting contest is here, June Circuits '19, a challenging challenge with 8 amazing problems, should be solved in 9 days. The contest will start on June 21, 15:30 PM UTC.

Thanks to problem setters for doing such a fantastic job, we have 7 setters involved this time (!):

I'm tester of the round, I'm completely sure that you'll enjoy too!

To make the challenge more interesting, we will add problems to the contest in this order:

  • Day 0: Very-Easy, Easy-medium, Approximation.
  • Day 2: Medium, Medium.
  • Day 4: Medium, Medium.
  • Day 6: Medium-Hard.

As usual, there will be some sweet prizes for the top five competitors:

  • First place: $100 Amazon gift card + HE t-shirt.
  • Second place: $75 Amazon gift card + HE t-shirt.
  • Third place: $50 Amazon gift card + HE t-shirt.
  • Fourth place: HE t-shirt.
  • Fifth place: HE t-shirt.

Hope to see you on the leaderboard!

 
 
 
 
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4 weeks ago, # |
  Vote: I like it +4 Vote: I do not like it

Last month's circuits was a disaster. The problem statements were ambiguous and even editorials weren't provided, only author's solution was there. Hope so everything is perfect this time!

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    4 weeks ago, # ^ |
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    We're sorry for the problems in the previous contests. We're doing our best every month to become better. We change something and test, discuss together and think a lot. You can help us with your feedback (as you're doing now). Thanks!

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      3 weeks ago, # ^ |
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      Hey Arpa, why aren't the editorials provided this time also?

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        3 weeks ago, # ^ |
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        They are ready, I asked someone to upload them. Not answered yet. I'm sorry.

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          3 weeks ago, # ^ |
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          Okay, we are waiting! And if possible, please also look into May Circuit's editorials too.

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4 weeks ago, # |
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Why can't I log in to site? When I enter credentials and click I get error 500 and I get it for every page I visit there. Clear cookies -> everything is fine. Log in again -> error 500. Is my account broken? Is that a known issue? :D

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    4 weeks ago, # ^ |
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    Hi. I'll deliver your message to the back-end team. Thanks for your patience.

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3 weeks ago, # |
  Vote: I like it +11 Vote: I do not like it

for question P5 — Altitudes, for following test case, 100 100 0 -1 -1 0

the expected output is shown as 0 but we can clearly see that solution exist and answer can not be zero. Please look into tester/setters solution.

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3 weeks ago, # |
Rev. 2   Vote: I like it +12 Vote: I do not like it

This is bit harsh, but You should have mentioned it in the announcement if this circuit was supposed to be educational.

  1. Rotation : No issues but fairly simple.

  2. Determine the Winner : Already appeared in codechef.

  3. GCD Problem : Seriously, You're not kidding us? This is so standard that I even included this in one blog post that I wrote.

  4. Function Value : Again classical.

  5. Queries Problem : Appeared in Contest on hackerearth/hackerrank (without updates).

  6. Altitutdes : This is okay.

  7. XOR Paths : Seriously? Just Paste the code for Xor Transformation.

I mean having almost all problems, which involves 0 thinking, and just pasting part of code from somwhere else is not how a round is supposed to be. :-)

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    3 weeks ago, # ^ |
      Vote: I like it +14 Vote: I do not like it

    The main purpose of Circuits is to learn new things, not a competitive contest. It has a wide time, so it's not to examine your ability or speed. It's for learning new things and become better.

    I didn't saw any of the problems before in online judges. But yes, to be fair, problems 2, 3, 7 were classical, it's the purpose of Circuits contests.

    I'm honored to have your ideas to make our contest better.

    Thanks for your feedback :)

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      3 weeks ago, # ^ |
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      Can you give some ideas on how to solve the last problem ?

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      3 weeks ago, # ^ |
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      @Arpa None of the editorials have even a single line of explanation. All they have is lines of code. Please look into the matter.

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        3 weeks ago, # ^ |
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        Please wait for several hours. Thanks for your patience.

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    3 weeks ago, # ^ |
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    i solved GCD problem because of your mobius inversion blog. XOR paths was new to me(xor fft ), Queries problem is also interesting too , can u tell where did u find it ?

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    3 weeks ago, # ^ |
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    i think long challenges are always supposed to be educational .

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3 weeks ago, # |
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How to get 100 points in Queries Problem? I got only 60 points by changing values to logarithms and then using binary search over a fenwick tree.

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    3 weeks ago, # ^ |
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    try this test case 1 1 1 1 100

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    3 weeks ago, # ^ |
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    The test cases are wrong. You'll lose precision while taking double. You'll have to submit multiple times, to guess what author has done, to get all 100 points.

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3 weeks ago, # |
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3 weeks ago, # |
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Can you please update the post with the link of editorial.

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    3 weeks ago, # ^ |
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    Editorials are in the editorial section of problems in the contest dashboard (example).