题库练习 Circus--Platinum
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A841 | Circus--Platinum

来源USACO
时间限制1s
内存限制128MB
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题目描述

The $N$ cows of Farmer John's Circus ($1 \leq N \leq 10^5$) are preparing
their upcoming acts. The acts all take place on a tree with vertices labeled
$1\ldots N$. The "starting state" of an act is defined by a number $1 \leq K
\leq N$ and an assignment of cows $1\dots K$ to the vertices of the tree, so
that no two cows are located at the same vertex.
In an act, the cows make an arbitrarily large number of "moves." In a move, a
single cow moves from her current vertex to an unoccupied adjacent vertex. Two
starting states are said to be equivalent if one may be reached from the other
by some sequence of moves.
For each $1 \leq K \leq N$, help the cows determine the number of equivalence
classes of starting states: that is, the maximum number of starting states
they can pick such that no two are equivalent. Since these numbers may be very
large, output their remainders modulo $10^9 + 7$.

输入格式

Line $1$ contains $N$.
Lines $2\le i\le N$ each contain two integers $a_i$ and $b_i$ denoting an edge
between $a_i$ and $b_i$ in the tree.

输出格式

For each $1\le i\le N,$ the $i$-th line of output should contain the answer
for $K=i$ modulo $10^9+7$.

输入输出样例

输入 #1
5
1 2
2 3
3 4
3 5
输出 #1
1
1
3
24
120
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