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AtCoder Regular Contest 203 (Div. 2) Announcement
By atcoder_official, history, 9 months ago, In English

We will hold AtCoder Regular Contest 203 (Div. 2).

The point values will be 400-500-600-800-800.

We are looking forward to your participation!

  • Vote: I like it
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  • Vote: I do not like it

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9 months ago, hide # |
 
Vote: I like it -30 Vote: I do not like it

D is unexpectedly easy.

My friend asked me what is needed for D. After thinking for a while, I told him "a few arrays and variables".

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

C is harder than the usual Div.2 Cs. Unfortunately I made some foolish mistakes in B so I got a low rank :(

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

ad-hoc round.

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9 months ago, hide # |
 
Vote: I like it +17 Vote: I do not like it

Screencast with commentary

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

In this editorial, $$$A_i=\lfloor \frac{M}{2} \rfloor(i \lt 1)$$$?

I think it may be (i>1)?

(Sorry for my poor English)

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9 months ago, hide # |
 
Vote: I like it +6 Vote: I do not like it

Problem B is good, but unfortunately I spent too much time on the case where there is only one single 1 in both arrays.

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9 months ago, hide # |
 
Vote: I like it 0 Vote: I do not like it 
swap {1,0} with {1} at a position to its right
swap {0,1} with {1} at a position to its right

How to simulate these operations?

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

    Find subarray $$$[1,0]$$$ (or $$$[0,1]$$$) and subarray $$$[1]$$$, then swap them. Number of inversions increases, so the process is finite

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

      Thanks. But I realized today that it is not necessary. We can always make the array look like 11...0... when there are more than 1 1's are present. So, I don't need to simulate it.

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

    Damn! 10 downvotes. How did I offend so many people by asking for an implementation?

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

about the editorial of C,why can we only replace these H-V-H movements with V’ but not a H'?I mean,of course I know they lead to different results,but what's the reason behind it that we must replace right-up-right by a down(not a right)?

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9 months ago, hide # |
 
Vote: I like it -10 Vote: I do not like it

Typo in A's editorial

it should be ceil(M/2) + (N-1)*floor(M/2)

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