给定一个正整数 $N$，求 $1$ 到 $N$ 的整数排列中最小环的期望长度。所有排列都是等概率出现的。
设答案为最简分数 $\frac{A}{B}$。输出 $A \cdot B^{-1} \bmod P$，其中 $P$ 是给定的质数。保证 $\gcd(B, P) = 1$。
输入仅包含一行，有两个整数 $N$ 和 $P$（$1 \le N \le 10^4$，$10^4 < P \le 10^9 + 33$）。保证 $P$ 是一个质数。
在一行中输出该问题的答案。
2 1000000007
500000005
3 1000000007
666666673
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