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#1084. 优美序列的解构

统计

你拥有一款名为“Beautiful Sequence Unraveler (BSU)”的强大工具。该工具专门处理“优美序列”。一个优美序列是指一个由 $n$ 个整数组成的数组 $a_1, a_2, \dots, a_n$,且满足以下条件:不存在任何整数 $i$ 满足 $1 \le i < n$ 且 $\max\{a_1, \dots, a_i\} = \min\{a_{i+1}, \dots, a_n\}$。

BSU 处理优美序列的能力很强,但你不知道这类序列出现的频率。因此,你想要计算在所有长度为 $n$、且元素均在 $1$ 到 $k$ 之间(包含 $1$ 和 $k$)的数组中,优美序列的数量。由于该数量可能很大,你需要将其对质数 $p$ 取模。

输入格式

仅一行,包含三个整数 $n, k, p$ ($1 \le n \le 400, 1 \le k \le 10^8, 998\,244\,353 \le p \le 10^9 + 9$)。

保证 $p$ 为质数。

输出格式

输出该问题的答案对 $p$ 取模的结果。

样例

样例输入 1

2 2 1000000007

样例输出 1

2

样例输入 2

3 4 1000000009

样例输出 2

36

样例输入 3

228 112263 998244353

样例输出 3

379700769

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