codechef MAY18 div2 部分题解

T1

https://www.codechef.com/MAY18B/problems/RD19

刚开始zz了，其实很简单。

删除一个数不会使gcd变小，于是就只有0/1两种情况

T2

https://www.codechef.com/MAY18B/problems/XORAGN

我们可以把B序列看做一个矩阵

那么$A(i,j)$和$A(j,i)$会抵消掉

因此答案就是$\sum_1^n A(i,i) + A(i,i)$

T3

https://www.codechef.com/MAY18B/problems/MTYFRI

答案的序列是固定的，因此后手会把自己最小的换做对手最大的，

贪心求解，两个堆维护最小最大值

T4

https://www.codechef.com/MAY18B/problems/DBFB

按照套路，考虑A，B对答案的贡献，A只可能作为第一项，B只可能作为第二项。

统计出斐波那契数列中A，B的出现次数

A，B会被枚举M次，因此答案最后乘M

T5

很有思维量的一道题

来不及写题解了，

弃坑。、

目前rank

顺便Orz zbq

原文地址：https://www.cnblogs.com/zwfymqz/p/8994189.html

时间： 2024-10-11 17:20:40

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