atcoder_official's blog

AtCoder Beginner Contest 322 Announcement
By atcoder_official, history, 15 months ago, In English

We will hold AtCoder Beginner Contest 322.

We are looking forward to your participation!

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  • Vote: I do not like it

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15 months ago, # |
  Vote: I like it +27 Vote: I do not like it

Note to self: Solve in this order A-B-D-E-C

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

I'm looking forward to seeing the problems of the contest! Atcoder has problems which are very interesting and useful for learning.

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Yeah, looking forward to getting a positive delta:D

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

why 7 problems instead of 8?

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    15 months ago, # ^ |
      Vote: I like it +2 Vote: I do not like it

    It changed from ABC319. See the post archive.

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Good luck with all the questions!

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15 months ago, # |
  Vote: I like it +3 Vote: I do not like it

Posting this with no context

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Writers of D and E I am coming to your house

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    15 months ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    E was easy,D was difficult,problem like F is also present in codeforces edu section.

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

How can we solve E using DP ? what's the state and transition

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15 months ago, # |
  Vote: I like it -9 Vote: I do not like it

What is the purpose for setting the problem D? It uses almost no algorithm!

E and F is both easier than D in coding, and D takes me more time.I don't think problems like D is good.

And also, F is an original problem in Luogu.

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    15 months ago, # ^ |
      Vote: I like it +28 Vote: I do not like it

    The purpose is to test your implementation skills and speed. These kinds of problems often require you to compose your code correctly into functions in order to save time spent writing code in the contest. I think they are good to have on occasion, but maybe better in contests that are a little longer.

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      15 months ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      True, but it is quite hard to write. Sad.

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    15 months ago, # ^ |
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    Which problem in Luogu is F?

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      15 months ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      P2572

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        15 months ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        thx, going to get double experiences now :)

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          15 months ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          In fact it is not the same one. Problem F is part of it:)

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15 months ago, # |
  Vote: I like it +5 Vote: I do not like it

fucking dirty D

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15 months ago, # |
  Vote: I like it +9 Vote: I do not like it

Is there a way to do F other than lazy bashing? Also D is the most awful implementation I have had the misfortune of solving

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

D is a good problem , but i dont like it. hope never see some as it again

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15 months ago, # |
← Rev. 2   Vote: I like it -6 Vote: I do not like it

what trash D and typical F......

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15 months ago, # |
  Vote: I like it +14 Vote: I do not like it

D is fkin implementation

E is fkin DP

F is fkin segtree template

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15 months ago, # |
  Vote: I like it +3 Vote: I do not like it

Problem F is so typical, it is even an exist problem.

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Is there some elegant less code solution for D? Otherwise the problem is just implementation hell.

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Sometimes you have to do some tedious works. D is just a reflection of life which is very educational.

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Can anyone explain how (if possible) I can improve my method to work for D. Basically, I'm tiling in a checkerboard manner, with the observation that if a polyomino is even, the black and white squares will match, so polarity can either be Odd Odd Even or Even Even Even. Then I check if it's possible to match up to equate. This fails on sample 3 and 3 other random cases. I refuse to believe that there's a non-brute force method, so can someone improve my code to AC? Thanks.

Here is a link to my submission:

https://atcoder.jp/contests/abc322/submissions/46104612

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15 months ago, # |
  Vote: I like it -27 Vote: I do not like it

trash D

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

First time for me to write a 11-level nested for-loop in a contest!

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15 months ago, # |
  Vote: I like it -15 Vote: I do not like it

Implementation of D insulted my implementation skill or is it trash itself ?

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

The D and E are not very good,they don't have many thinking difficulty, but need a lot of code

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15 months ago, # |
  Vote: I like it -18 Vote: I do not like it

Immediately after looking at D, I didn't want to solve it.

After looking at evima's video editorial, I just want to think that the task never existed in all history.

Like seriously what is this abomination

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15 months ago, # |
← Rev. 2   Vote: I like it 0 Vote: I do not like it

F is an old problem (it is a easy version of SCOI2010 序列操作(SC, Sichuan, is a province of China)).

I think E is better, the trick is not very very easy to think of.

D is hard to write.

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15 months ago, # |
← Rev. 2   Vote: I like it +6 Vote: I do not like it

Tests for problem D are a bit weak. For example, this submission is wrong because if all three pieces overlap at the same place, it will be judged as correct. The following test can hack it.

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upd: There is another problem with the code, I have no idea how it could possibly have passed. Hack:

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    15 months ago, # ^ |
      Vote: I like it +10 Vote: I do not like it

    The given polyominoes are connected. In other words, the squares that make up a polyomino can be reached from each other by following only the squares up, down, left, and right.

    It seems that the first polyomino of the second hack violates the constraints.

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15 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Some people cheat in problem F. Like this submission, it is nearly the same as the first article in the luogu tutorial.

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