CF1603E.A Perfect Problem
普及/提高-
通过率:0%
AC君温馨提醒
该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。
题目描述
A sequence of integers b1,b2,…,bm is called good if max(b1,b2,…,bm)⋅min(b1,b2,…,bm)≥b1+b2+…+bm .
A sequence of integers a1,a2,…,an is called perfect if every non-empty subsequence of a is good.
YouKn0wWho has two integers n and M , M is prime. Help him find the number, modulo M , of perfect sequences a1,a2,…,an such that 1≤ai≤n+1 for each integer i from 1 to n .
A sequence d is a subsequence of a sequence c if d can be obtained from c by deletion of several (possibly, zero or all) elements.
输入格式
The first and only line of the input contains two space-separated integers n and M ( 1≤n≤200 ; 108≤M≤109 ). It is guaranteed that M is prime.
输出格式
Print a single integer — the number of perfect sequences modulo M .
输入输出样例
输入#1
2 998244353
输出#1
4
输入#2
4 100000007
输出#2
32
输入#3
69 999999937
输出#3
456886663
说明/提示
In the first test case, the perfect sequences are [2,2] , [2,3] , [3,2] and [3,3] .
In the second test case, some of the perfect sequences are [3,4,3,5] , [4,5,4,4] , [4,5,5,5] etc. One example of a sequence which is not perfect is [2,3,3,4] , because, for example, the subsequence [2,3,4] is not an good as 2⋅4<2+3+4 .