2018-2019 Russia Open High School Programming Contest

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Revision as of 12:50, 12 December 2018 by Kblack (talk | contribs) (→‎Problem K)
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Problem A

Solved by kblack. 00:17 (+1)

温暖的签到。

Problem B

Solved by ultmaster. 01:09 (+)

题意:将若干字符串按照某种解析到的规则排列起来。

题解:字符串解析模拟。

Problem C

Solved by ultmaster. 03:57 (+1)

Problem D

Solved by zerol. 01:18 (+)

Problem E

Solved by kblack. 02:11 (+)

Problem F

Upsolved by ultmaster.

题意:有 $n$ 个数让你猜,每次询问三个下标,回答你这三个下标上的数的最大值和最小值的和。要求在 $4n$ 次内猜出来。

题解(无脑):考虑 $n=5$ 的做法,总共能拿到 10 份信息,暴力枚举顺序后,列出方程,用高斯消元解出来,判合法性。然后 5 个 5 个做下去就好了。

全真模拟现场赛意识模糊写不了题的症状。

Problem I

Solved by zerol. 00:47 (+1)

Problem K

Solved by kblack. 01:28 (+)

题意:定义一个关系,一个串表示 ABBBBB,定义互相是子序列的可以在一组,求分最小组数。

题解:容易发现这个关系是自反对称且传递的,所以划分即是答案,每个串表示为 B 部分每个字母是否出现以及 A 部分去除在 B 中出现的后缀字母。

Problem L

Solved by zerol. 02:22 (+)

Problem M

Solved by kblack. 00:04 (+)

温暖的签到。