There are many integer sequences in the world, and your mission is to find how many sequences are good.
An integer sequence $$$a_i$$$ of length $$$n$$$ is good if and only if all of these conditions holds:
Where $$$S_i = \sum_{j=1}^i a_j$$$.
You will be given $$$n$$$ and $$$m$$$, and it is guaranteed that $$$m$$$ is odd.
Since the answer may be very large, you should calculate it modulo $$$998\, 244\, 353$$$.
The only line contains two integers $$$n$$$ and $$$m$$$ ($$$1 \le n \le 10^7$$$, $$$1 \le m \leq 2n$$$, $$$m$$$ is odd).
Output a single integer — the number of good sequences meeting the constraints, modulo $$$998\, 244\, 353$$$.
9 13
124
500 999
195157058
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