CF1603E.A Perfect Problem

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题目描述

A sequence of integers b1,b2,,bmb_1, b_2, \ldots, b_m is called good if max(b1,b2,,bm)min(b1,b2,,bm)b1+b2++bmmax(b_1, b_2, \ldots, b_m) \cdot min(b_1, b_2, \ldots, b_m) \ge b_1 + b_2 + \ldots + b_m .

A sequence of integers a1,a2,,ana_1, a_2, \ldots, a_n is called perfect if every non-empty subsequence of aa is good.

YouKn0wWho has two integers nn and MM , MM is prime. Help him find the number, modulo MM , of perfect sequences a1,a2,,ana_1, a_2, \ldots, a_n such that 1ain+11 \le a_i \le n + 1 for each integer ii from 11 to nn .

A sequence dd is a subsequence of a sequence cc if dd can be obtained from cc 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 nn and MM ( 1n2001 \le n \le 200 ; 108M10910^8 \le M \le 10^9 ). It is guaranteed that MM is prime.

输出格式

Print a single integer — the number of perfect sequences modulo MM .

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, 2] , [2,3][2, 3] , [3,2][3, 2] and [3,3][3, 3] .

In the second test case, some of the perfect sequences are [3,4,3,5][3, 4, 3, 5] , [4,5,4,4][4, 5, 4, 4] , [4,5,5,5][4, 5, 5, 5] etc. One example of a sequence which is not perfect is [2,3,3,4][2, 3, 3, 4] , because, for example, the subsequence [2,3,4][2, 3, 4] is not an good as 24<2+3+42 \cdot 4 < 2 + 3 + 4 .

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