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#7135. 色数

统计

bobo 有一个连通图 $G$,他想用 $c$ 种颜色中的一种为每个顶点着色,使得没有两个相邻的顶点具有相同的颜色。

求着色方案数,结果对 $(10^9 + 7)$ 取模。

输入格式

第一行包含 3 个整数 $n, m, c$,分别表示顶点数、边数和颜色数($1 \le n \le 10^5, n - 1 \le m \le n + 8, 1 \le c \le 10^9$)。

顶点编号为 $1, 2, \dots, n$。

接下来的 $m$ 行,每行包含 2 个整数 $a_i, b_i$,表示顶点 $a_i$ 和 $b_i$ 之间的一条边($1 \le a_i, b_i \le n, a_i \neq b_i$)。

输出格式

输出一个整数,表示着色方案数。

样例

样例输入 1

3 3 3
1 2
2 3
3 1

样例输出 1

6

样例输入 2

4 3 1000000000
1 2
2 3
3 4

样例输出 2

3584

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