AT_arc228_e [ARC228E] Pair of Permutations
Description
Find the number, modulo $ 998244353 $ , of pairs of permutations $ (P,Q)=((P_1,P_2,\dots,P_N),(Q_1,Q_2,\dots,Q_N)) $ of $ (1,2,\dots,N) $ satisfying the following condition.
- $ P_i \le i+M $ , $ Q_i \le i+M $ , and $ P_i \neq Q_i $ all hold for every integer $ i $ satisfying $ 1 \le i \le N $ .
Input Format
The input is given from Standard Input in the following format:
> $ N $ $ M $
Output Format
Output the answer.
Explanation/Hint
### Sample Explanation 1
The pairs $ (P,Q) $ satisfying the condition are the following four pairs.
- $ P = (1,2,3),Q = (2,3,1) $
- $ P = (1,3,2),Q = (2,1,3) $
- $ P = (2,3,1),Q = (1,2,3) $
- $ P = (2,1,3),Q = (1,3,2) $
### Constraints
- $ 2 \le N \le 10^9 $
- $ 1 \le M \le 125000 $
- All input values are integers.