Difference between revisions of "ICPC 2019 Nanjing Online Contest"

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(Created page with "== Problem A == Solved by Xiejiadong. 02:41 (+) == Problem B == Solved by Weaver_zhu && Kilo_5723. 03:01 (+9) == Problem C == Solved by Weaver_zhu. 02:20 (+) == Problem...")
 
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Solved by Xiejiadong. 02:41 (+)
 
Solved by Xiejiadong. 02:41 (+)
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题意:蛇形矩阵中有 $n$ 个位置是有价值的,价值是位置上的数位和,每次询问一个子矩阵中的价值总和。
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题解:蛇形矩阵,给出坐标求位置上的数,可以直接 $O(1)$ 通过分类讨论出来。
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只需要知道他是从内往里第几圈就能算出来。
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得到了每一个位置的价值,就变成了一个二维数点问题,直接树状数组维护一下就好了。
  
 
== Problem B ==
 
== Problem B ==

Revision as of 10:10, 1 September 2019

Problem A

Solved by Xiejiadong. 02:41 (+)

题意:蛇形矩阵中有 $n$ 个位置是有价值的,价值是位置上的数位和,每次询问一个子矩阵中的价值总和。

题解:蛇形矩阵,给出坐标求位置上的数,可以直接 $O(1)$ 通过分类讨论出来。

只需要知道他是从内往里第几圈就能算出来。

得到了每一个位置的价值,就变成了一个二维数点问题,直接树状数组维护一下就好了。

Problem B

Solved by Weaver_zhu && Kilo_5723. 03:01 (+9)

Problem C

Solved by Weaver_zhu. 02:20 (+)

Problem D

Solved by Kilo_5723. 02:10 (+)

Problem E

Unsolved. (-5)

Problem F

Solved by Xiejiadong. 00:50 (+)

Problem G

Unsolved.

Problem H

Solved by Kilo_5723 && Xiejiadong. 01:12 (+)

Problem I

Unsolved.