AtCoder Regular Contest 155
翻译中…
Problem Statement
翻译中…
You are given a sequence of $N$ non-negative integers: $D=(D_1, D_2, \dots, D_N)$.
翻译中…
Find the number of labeled trees with $N$ vertices numbered $1$ to $N$ that satisfy the following condition, modulo $998244353$.
翻译中…
- There is a way to direct the
$N-1$edges so that the outdegree of each vertex$i\ (1\leq i \leq N)$is$D_i$.
翻译中…
Constraints
翻译中…
$2 \leq N \leq 2 \times 10^5$$0 \leq D_i \leq N-1$$\sum_{i=1}^{N} D_i = N-1$- All values in the input are integers.
翻译中…
Input
翻译中…
The input is given from Standard Input in the following format:
翻译中…
N
D_1 D_2 \dots D_N
翻译中…
Output
翻译中…
Print the answer.
翻译中…
样例
Input #1
4
0 1 0 2
Output #1
5
Below are the five trees that satisfy the condition, directed in a desired way.

Input #2
5
0 1 1 1 1
Output #2
125
Input #3
15
0 0 0 0 0 0 0 1 1 1 1 1 2 3 4
Output #3
63282877
题目信息
题面与样例版权归 AtCoder 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。