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gabrielwu's blog

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

If you are interested in participating in the Montgomery Blair Informatics Tournament, which will be held online from 1:00-4:00 PM EDT on Sunday (6/7/20), please register at https://mbit.mbhs.edu/.

Teams of up to 4 are allowed! Anyone can compete, but only teams of US high school (or middle school) students can win Amazon gift cards for prizes:

  • $50 per person for 1st place in Advanced Division

  • $25 per person for 1st place in Standard Division, 2nd place in Advanced Division, and 3rd place in Advanced Division

If you want to get a sense of what mBIT problems are like, take a look at the problems from our contest last November:

Message me or email mbit.organizers@gmail.com if you have any questions!

UPDATE: The contest is over! You can view all results on our website.

Here are the problems:
Standard problems
Advanced problems

You can test out your solutions by submitting to these CF contests:
Standard contest
Advanced contest

Here are the editorials and solutions:
Standard solutions
Advanced solutions

We sincerely apologize with for the technical difficulties, and are working to ensure it doesn't happen again. Thank you to everyone who competed!

 
 
 
 
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4 weeks ago, # |
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4 weeks ago, # |
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I assume it's supposed to be (6/7/20)?

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Is it rated?

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4 weeks ago, # |
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Wow, what an amazing opportunity for teams of US high school or middle school students! It's a shame that I can't win any prizes, since I'm from Australia, but I'll be sure to stop by to check out some high-quality problems by high-quality problemsetters :)

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Wow, I’m excited!

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Seems interesting.

May I ask how the divisions compare to Codeforces divisions? That might help some people gauge difficulty if they don't have time to look at the sample problems.

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    4 weeks ago, # ^ |
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    Standard is comparable to Div 3/Div 2 ABC.

    Advanced is comparable to Div 2/Div 1.

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      4 weeks ago, # ^ |
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      I would say that Advanced is harder than that. It probably ranges from Div 2 C to Div 1 E.

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Wow, celebrating the 10 year anniversary (plus a few days) of me graduating, very classy. :)

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is the website working well?

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    4 weeks ago, # ^ |
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    Our website is having some trouble. It should be back up soon.

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Anyone able to access the website?

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    4 weeks ago, # ^ |
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    Not yet, sorry. We're working on it.

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      4 weeks ago, # ^ |
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      Can we expect some hints/editorials to the problems after the contest ends? or atleast access to solutions? I don't wish to attempt it if otherwise is the case. :sweat_smile:

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        4 weeks ago, # ^ |
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        Yes, we will release editorials after the contest ends.

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I can submit code but it seems like the verdicts won't load.

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I can't see the verdict, getting not found error page :/

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Will problems be made available to upsolve?

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    4 weeks ago, # ^ |
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    Yes, I have updated the post with the links.

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      4 weeks ago, # ^ |
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      Thank you, I enjoyed the problems and this contest. Apart from the technical issues, the team did a great job.

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Is there any way we can get our submissions?

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    4 weeks ago, # ^ |
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    You can see the results on the leaderboard. If you really want to see the code you submitted for a specific problem, you can email us and we'll try to look for it (no guarantees though).

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Also, what was the logic in hen hackers?

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    4 weeks ago, # ^ |
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    The Hen Hackers solution was based around the following: First find out which letters are present in the solution (62 queries) Then, use length two queries as a comparator in a sorting algorithm. For example, to find out if a is before b ask "ab". This takes O(nlogn) queries. By the end, you will have sorted the password.

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      4 weeks ago, # ^ |
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      This is soo cool!!

      I was trying the $$$O(n^2)$$$ sort + some optimizations. Never struck me to use it as a comparator in gcc sort!!

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        4 weeks ago, # ^ |
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        Glad you enjoyed the problem! I had fun writing it.

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        I spent some good time doing some random_shuffle to try to find the right place, and then I realized the binary search.

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Would it be possible to add the problem names to the CF contests? Right now they are just "A -", "B -", etc.

(And if it would be possible to add the PDF in the CF contest that would be nice.)

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    4 weeks ago, # ^ |
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    Yep, I've updated the problems and attached the statements under contest materials. Let me know if I made any errors.

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      Thanks, makes it much easier to use! Appreciate it.

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gabrielwu by when will the editorials of the advanced problems be published?

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    4 weeks ago, # ^ |
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    We are currently finalizing the editorials and will publish them shortly.

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    3 weeks ago, # ^ |
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    Editorials are now published. See the updated post.

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is the editorial published yet? if it is, can anyone please provide the link to that?

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    Not yet. I will update the blog when it's ready.

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    3 weeks ago, # ^ |
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    Editorials have just been published. See the updated post.

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