AtCoder Regular Contest 212 (Div. 2)
翻译中…
Problem Statement
翻译中…
You are given integers $N,M,X$.
翻译中…
Perform the following series of operations to create a sequence $A$ of length $N$ consisting of non-negative integers.
翻译中…
- Freely decide an integer sequence
$A=(A_1,A_2)$of length$2$. - Then, perform the following operation
$N-2$times on$A$.
翻译中…
A sequence $A$ is a good sequence if and only if it satisfies the following:
翻译中…
$0 \le A_i \le M \ (1 \le i \le N)$$A_N=X$
翻译中…
Find the sum, modulo $998244353$, of $A_1 \times A_2$ over all good sequences that can be obtained by the operations.
翻译中…
Constraints
翻译中…
$3 \leq N \leq 2 \times 10^5$$1 \leq X \leq M \leq 2 \times 10^5$- All input values are integers.
翻译中…
Input
翻译中…
The input is given from Standard Input in the following format:
翻译中…
N M X
翻译中…
Output
翻译中…
Output the answer.
翻译中…
样例
Input #1
3 4 3
Output #1
8
Some possible sequences are $(0,3,3),(1,4,3),(2,1,3)$.
The sum of $A_1 \times A_2$ over all possible sequences is $8$.
Input #2
150000 160000 140000
Output #2
791841701
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。