Difference between revisions of "ICPC 2019 Nanjing Online Contest"
Jump to navigation
Jump to search
Xiejiadong (talk | contribs) (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...") |
Xiejiadong (talk | contribs) |
||
Line 2: | Line 2: | ||
Solved by Xiejiadong. 02:41 (+) | 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 == | == 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.