P25118 [AtCoder] Pass to Next
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题目描述

Problem Statement

$N people called Person 1, 2, \ldots, N$ are standing in a circle.
For each $1 \leq i \leq N-1, Person i$'s neighbor to the right is Person i+1, and Person N's neighbor to the right is Person 1.
Person i initially has a_i balls.
They will do the following procedure just once.

  • Each person chooses some (possibly zero) of the balls they have.
  • Then, each person simultaneously hands the chosen balls to the neighbor to the right.
  • Now, make a sequence of length N, where the i-th term is the number of balls Person i has at the moment.

Let S be the set of all sequences that can result from the procedure. For example, when a=(1,1,1), we have S= {(0,1,2),(0,2,1),(1,0,2),(1,1,1),(1,2,0),(2,0,1),(2,1,0) }.
Compute $\sum_{x \in$ $S} \prod_{i=1}^{N} x_i, modulo 998244353$.

Input

Input is given from Standard Input in the following format:
N
$a_{1} a_{2} \cdots a_{N}$

Output

Print $\sum_{x \in$ $S} \prod_{i=1}^{N} x_i, modulo 998244353$.

Constraints

  • All values in input are integers.
  • $3 \leq N \leq 10^5$
  • $0 \leq a_i \leq 10^9$

Sample Input 1

3
1 1 1

Sample Output 1

1

  • We have S= {(0,1,2),(0,2,1),(1,0,2),(1,1,1),(1,2,0),(2,0,1),(2,1,0) }.
  • $\sum_{x \in$ $S} \prod_{i=1}^{N} x_i$ is 1.

Sample Input 2

3
2 1 1

Sample Output 2

6

Sample Input 3

20
5644 493 8410 8455 7843 9140 3812 2801 3725 6361 2307 1522 1177 844 654 6489 3875 3920 7832 5768

Sample Output 3

864609205

  • Be sure to compute it modulo 998244353.
输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
3 1 1 1
样例输出
1