Блог пользователя Muhammad_mhs

Автор Muhammad_mhs, история, 3 года назад, По-английски
Please! Can anyone tell me in which case my solution is being WA?

My Solution: 132257155

Thanks in advance.

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3 года назад, # |
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This was posted by ExplodingFreeze in the contest's comments section. I hope it is helpfull

_Are you checking if cells which are X would be theoretically exitable if they weren't X as well?

Suppose one of those cells is not exitable even if it wasn't X, then you wouldn't be able to 
differentiate between it being initially marked X or not, so the grid isn't determinable.

I forgot about this and got WA3 because of that._
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3 года назад, # |
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Hey since you have done the question now, can you please tell what kind of case was causing you to get wrong answer on test 3(143rd token). Even i am getting a wrong answer there and am not able to figure it out.

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    3 года назад, # ^ |
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    Hello, he has a bad case in subcase 143 of the third case and maybe it is related to the following (posted by vrintle in the comments section)

    _Because, we can't determine the state of (2,2) cell exactly without looking at the grid. 
    Suppose, instead of
    
    XX  
    XX
    We're given,
    
    XX  
    X.
    
    Then, still none are exitable, but one cell in the latter is empty. So, undeterminable!_

    I hope it is what you are looking for :)

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      3 года назад, # ^ |
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      Thank you for your help. I was only checking the condition of top=='X' and left=='X' for a empty cell. Turns out that i needed to check for even filled cells. Honestly it pains to know that changing only one line can get your solution accepted but you didnt notice that one line in contest. Thanks for your help tough.

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        3 года назад, # ^ |
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        That happens often unfortunately, but it is the only way to improve the ability to identify corner cases quickly 〜(꒪꒳꒪)〜.

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    3 года назад, # ^ |
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    I do not find the Case in which case I was wrong. But During contest time I try with iterative dp. My AC code was with recursive dp.