#AT1828. F - Tree Patrolling
F - Tree Patrolling
F - Tree Patrolling
Score : $600$ points
Problem Statement
You have a tree with $N$ vertices, numbered $1$ through $N$. The $i$-th edge connects Vertex $u_i$ and Vertex $v_i$.
You will choose some vertices (possibly none) and place a takahashi in each of them to guard the tree. A takahashi placed at Vertex $x$ will guard $x$ itself and the vertices directly connected to $x$ by an edge.
There are $2^N$ ways to choose vertices for placing takahashi. In how many of them will there be exactly $K$ vertices guarded by one or more takahashi?
Find this count and print it modulo $(10^9+7)$ for each $K=0,1,\ldots,N$.
Constraints
- $1 \leq N \leq 2000$
- $1 \leq u_i \lt v_i \leq N$
- The given graph is a tree.
- All values in input are integers.
Input
Input is given from Standard Input in the following format:
Output
Print $N+1$ lines. The $i$-th line should contain the answer for $K=i-1$.
3
1 3
1 2
1
0
2
5
There are eight ways to choose vertices for placing takahashi, as follows:
- Place a takahashi at no vertices, guarding no vertices.
- Place a takahashi at Vertex $1$, guarding all vertices.
- Place a takahashi at Vertex $2$, guarding Vertices $1$ and $2$.
- Place a takahashi at Vertex $3$, guarding Vertices $1$ and $3$.
- Place a takahashi at Vertices $1$ and $2$, guarding all vertices.
- Place a takahashi at Vertices $1$ and $3$, guarding all vertices.
- Place a takahashi at Vertices $2$ and $3$, guarding all vertices.
- Place a takahashi at all vertices, guarding all vertices.
5
1 3
4 5
1 5
2 3
1
0
2
5
7
17
10
6 10
1 8
2 7
5 6
3 8
3 4
7 10
4 9
2 8
1
0
3
8
15
32
68
110
196
266
325