MiptLited's blog

By MiptLited, 3 months ago, translation, In English,

The Moscow Institute of Physics and Technology welcomes high school students to take part in the programming boot camp Moscow Workshops Juniors! The boot camp will be held from February, 25 to March, 6.

The educational program includes daily studying contests, thematic lectures and practice. In a free time participants could join the popular science lectures, do sports, play the intellectual games and be involved in other activities. According to the results of the introductory contest the participants are divided into divisions depending on their skill level. Participants can choose the most interesting topics and make an appropriate training program. If a participant finds the curriculum too simple or difficult, he can change division.

To take part in the camp, you have to pass qualifying online tours, its format is close to the Olympiad in Informatics. You can participate in several rounds or only in one tour, the ranking of the participants is made according to the results of four rounds. The selection rules can be found by the link.

There are four qualifying rounds:

October, 27 at 16:00 pm UTC+03

November, 18 at 12:00 pm UTC+03

December, 16 at 12:00 pm UTC+03

January, 20 at 12:00 pm UTC+03

Moscow Workshops Juniors suggests awarded high school students several opportunities of participation. If you are a prize-winner of national Olympiads in informatics 2017-2018, you are invited to take part in the Workshops free of charge! For participants of national Olympiads in informatics 2017-2018 the Workshops cost $400, for another participants – $700

REGISTRATION

Have questions still? Write to organizing committee email: zksh-team@phystech.edu

 
 
 
 
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3 months ago, # |
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There is a limit for character count in the application page. For example, I can't paste my codeforces account link or my school name.

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3 months ago, # |
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MIPT is the best university!

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3 months ago, # |
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Your code here...
Ngu Loz
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3 months ago, # |
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So the Octomber one is just the trial round or an actual qualification round? (the first qual. round is "temporarily unavailable")

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3 months ago, # |
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Is there a tutorial for the first round? and can we discuss problems now?

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3 months ago, # |
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How about the accomodation ? How much is it and where ?

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3 months ago, # |
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Can anyone describe the solution for problem D: Presents?

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    3 months ago, # ^ |
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    You need to find n smallest linear combinations of presents. For this, I used set<pair<int,int>> to store price and linear combination hash. Hash was just sum of random weights assigned for each present. Initially set was with {{0,0}}. I just removed a minimal element (x,y) from set n + 1 times and added elements (x + p[i], y + w[i]) to the set and added x to the answer. w[i] is just a random value assigned to each present.

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      3 months ago, # ^ |
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      isn't there a high probability that there would be a hash-collision as it is just a linear combination of random weights. I feel like a collision would be frequent.

      Maybe it can be reduced by storing a triplet in the set and for each present have two different random weights.

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        3 months ago, # ^ |
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        Yes, you could store multiple hashes, but as I have seen, random weights are expected to work almost all of the times. It is quite unpredictable. I don't know if any anti hash anti-hash tests exist. Thinking about the ways to check collisions I came up with a trie-ish idea. You could store those linear combinations in a trie (moving down one node means adding some present) and you would only need to store O(1) data to be able to recover a full linear combination. It would be harder to implement and probably a lot slower. And we need to store only up to 1000 best linear combinations at a time if the hash is a random 64-bit integer collision should not occur.

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          3 months ago, # ^ |
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          Assuming that the both the numbers in the tuple randomly and uniformly vary between 1 to 1e9, then there are 1e18 total combinations. Probability of a collision for n numbers would be about n^2*(1e-18) which is basically 0. However, I am not sure how good the assumption is.

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            3 months ago, # ^ |
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            You should use birthday paradox to find the exact probability.

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              3 months ago, # ^ |
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              Yes. In my calculation I assumed there would be n^2 comparisons(although there are actually nC2 comparisons). Each comparison has 1e-18 probability of collision. Hence I multiplied n^2*1e-18.

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3 months ago, # |
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If someone needs the solutions for the problems from the first qualification, here are mine:
Problem A
Problem B
Problem C
Problem D
Problem E
Problem F

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2 months ago, # |
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Is there public standings available somewhere? (Past contests and an ongoing one)

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    2 months ago, # ^ |
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    Do you mean ongoing icpc workshop standings? This is a topic for school students.

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      2 months ago, # ^ |
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      Oops, the wrong topic indeed :) Supposed to ask in a different one :) Yep I meant the ongoing icpc workshop.

      UPD found them, now there're links from the main webpage of the workshop

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2 months ago, # |
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It shows that the contest started in e-judge and 2 hours remaining. In the mail and that blog time of the contest is 12:00 PM UTC +3 which is 1 hour from now. What's happening?

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    2 months ago, # ^ |
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    Only russian statements too.

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      2 months ago, # ^ |
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      Now it shows that private contest or wrong division error. Will there be a contest with English statements?

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        2 months ago, # ^ |
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        On top there is this line: [Moscow Workshops Junior 2019 Second Selection Round (ранний старт)] [Moscow Workshops Junior 2019 Second Selection Round (early start)]

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    2 months ago, # ^ |
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    For me it shows WRONG DIVISION or PRIVATE CONTEST

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2 months ago, # |
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The official link for the Selection 2.

The contest 942 occassionally was opened some time before the official start, so now it is closed (except for those several contestants who submitted in there).

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2 months ago, # |
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Pretty nice, huh?

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    2 months ago, # ^ |
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    The inconsistent results will be banned. And with very high chances only the number of the solved problems will matter in this qualification round.

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2 months ago, # |
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Is intended complexity for F (with 2-Sat + binary search)?

If yes, I think the time limit is awful and I'm really curious why organizers set it to just 4 sec.

(link to TL30 solution)

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    2 months ago, # ^ |
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    Intended complexity is . One of the jury solutions takes less than one second.

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      2 months ago, # ^ |
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      Can you share the solution?

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        2 months ago, # ^ |
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        One part of 2-sat edges are between points with the same x/y coordinate, you can find nearest ones in O(nlogn). Another part is between nodes with max(abs(x-x1),abs(y-y1))<=d, It can be shown that it is sufficient to use edges in MST with weights max(abs(x-x1), abs(y-y1)). I think that MST is a subset of the edges then you sort points by (y + x, y — x) in all four possible ways and then, while inserting a point, make the edge to the closest point.

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2 months ago, # |
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Hello everyone!

Due to technical problems in the 2nd qualifying round there will be an additional qualifying round — November, 25 at 12:00 pm UTC+03.

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    2 months ago, # ^ |
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    Did top 40 from the 2nd qualifying round (November 18) qualified for the camp?

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    2 months ago, # ^ |
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    What does pink colored name in the standings mean?

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2 months ago, # |
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High-level organization

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5 weeks ago, # |
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It seems that the round is planned to begin at 12:00 Moscow time, contrary to what we were announced in the last e-mail. "December 16 at 16:00 Moscow time."

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5 weeks ago, # |
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Can anyone explain the solution for problem B in the third qualification round which was held today?

Thanks in advance :)