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#7258. 随机游走

统计

有一个无限大的二维方格网格。网格上的坐标由一对整数 $(i, j)$ 表示。

Snuke 想要进行一次随机游走。他从 $(0, 0)$ 出发,共走 $N$ 步。当他位于 $(i, j)$ 时,下一步的位置将是 $(i-1, j)$、$(i, j-1)$、$(i, j+1)$ 和 $(i+1, j)$ 中的一个。每种可能性发生的概率均为 $\frac{1}{4}$。

设 $E$ 为随机游走过程中访问过的不同单元格数量的期望值。计算 $E \times 4^N$ 对 $M$ 取模的结果(该值保证为整数)。注意,$(0, 0)$ 始终被视为已访问。

输入格式

输入包含两个整数 $N$ 和 $M$ ($1 \le N \le 5000$, $10^9 \le M \le 2 \times 10^9$)。

输出格式

在一行中输出答案。

样例

样例输入 1

2 1000000007

样例输出 1

44

样例输入 2

2015 2000000000

样例输出 2

1892319232

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