题目描述
Problem Statement
You are given integers N and M.
Find the number of arrays $A=[A_1, A_2, \ldots, A_N]$ of length N such that the following conditions hold:
- $2 \le A_i \le M (1 \leq i \leq N)$
- There exists $a permutation P=[P_1,P_2,\ldots,P_N]$ of integers from 1 to N with the following property:
- For every i from 1 to N, A_i equals the length of the longest increasing subsequence of the sequence $[P_1, P_2, \ldots, P_{i-1}, P_{i+1}, \ldots, P_{N-1}, P_N]$.
As this number can be very large, output it modulo some prime Q.
Input
Input is given from Standard Input in the following format:
N M Q
Output
Print the answer modulo Q.
Constraints
- $3 \le N \le 5000$.
- $2 \le M \le N-1$.
- $10^8 \le Q \le 10^9$
- Q is a prime.
Sample Input 1
3 2 686926217
Sample Output 1
1
The only such array is [2, 2, 2], for which exists a permutation [1, 2, 3].
Sample Input 2
4 3 354817471
Sample Output 2
9
There are 9 such arrays: [2, 2, 2, 2], [2, 2, 2, 3], [2, 2, 3, 2], [2, 2, 3, 3], [2, 3, 2, 2], [2, 3, 3, 2], [3, 2, 2, 2], [3, 3, 2, 2], [3, 3, 3, 3].
Sample Input 3
5 2 829412599
Sample Output 3
1
The only such array is [2, 2, 2, 2, 2].
Sample Input 4
5 3 975576997
Sample Output 4
23
Sample Input 5
69 42 925171057
Sample Output 5
801835311
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分