atcoder_official's blog

By atcoder_official, history, 3 years ago, In English

We will hold AtCoder Beginner Contest 322.

We are looking forward to your participation!

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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Yeah, looking forward to getting a positive delta:D

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

why 7 problems instead of 8?

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3 years ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Good luck with all the questions!

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3 years ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

Posting this with no context

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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
 
Vote: I like it +5 Vote: I do not like it

fucking dirty D

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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
Rev. 2  
Vote: I like it -6 Vote: I do not like it

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

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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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Sometimes you have to do some tedious works. D is just a reflection of life which is very educational.

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3 years ago, hide # |
 
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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3 years ago, hide # |
 
Vote: I like it -27 Vote: I do not like it

trash D

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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
 
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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3 years ago, hide # |
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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3 years ago, hide # |
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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    3 years ago, hide # ^ |
     
    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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3 years ago, hide # |
 
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.