#dpp. [dp_p]Independent Set
[dp_p]Independent Set
Problem Statement
There is a tree with vertices, numbered . For each (), the -th edge connects Vertex and .
Taro has decided to paint each vertex in white or black. Here, it is not allowed to paint two adjacent vertices both in black.
Find the number of ways in which the vertices can be painted, modulo .
Constraints
- All values in input are integers.
- The given graph is a tree.
Input
Input is given from Standard Input in the following format:
Output
Print the number of ways in which the vertices can be painted, modulo .
Sample Input 1
3
1 2
2 3
Sample Output 1
5
There are five ways to paint the vertices, as follows:
Sample Input 2
4
1 2
1 3
1 4
Sample Output 2
9
There are nine ways to paint the vertices, as follows:
Sample Input 3
1
Sample Output 3
2
Sample Input 4
10
8 5
10 8
6 5
1 5
4 8
2 10
3 6
9 2
1 7
Sample Output 4
157