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4275:Color the Tree

题目描述
Now you have a tree with N vertices, and M pens with different color. You want to paint the vertices by your pens, and wondered that how many kinds of different colored trees could be resulted after painting.
Pay attention that two isomorphic trees having same color in corresponding vertices could be considered as two same colored trees.
输入解释
There are multiple test cases.
The first line contains two integers N and M. (1 <= N<=50,000,1<= M <= 100,000)
The next N - 1 lines each line contains two integer Ai and Bi indicating there is one tree edge between Ai and Bi. (1 <= Ai, Bi <= N)
输出解释
For each test case, output a number module 1000000007 (1e9 + 7) indicating the answer.
输入样例
1 3

2 3
1 2

5 2
1 2
1 3
3 4
3 5
输出样例
3
6
24
来自杭电HDUOJ的附加信息
Recommend liuyiding

该题目是Virtual Judge题目,来自 杭电HDUOJ

源链接: HDU-4275

最后修改于 2020-10-25T23:11:58+00:00 由爬虫自动更新

共提交 0

通过率 --%
时间上限 内存上限
2000/1000MS(Java/Others) 327680/327680K(Java/Others)