Problem9181--ABC204 —— F - Hanjo 2

9181: ABC204 —— F - Hanjo 2

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

We have a rectangular room that is $H$ meters long and $W$ meters wide.  
We will fill this entire room with tatami (rectangular mats) that are $2$ meters long and $1$ meter wide, and hanjo (square mats) that are $1$ meter long and $1$ meter wide. Each tatami can be placed vertically or horizontally.  
How many ways are there to fill the room?  
We distinguish ways that match only after rotation or reflection.

Since the count can be enormous, find it modulo $998244353$.

Input

Input is given from Standard Input in the following format:

```
$H$ $W$
```

Output

Print the answer.

Constraints

-   $1 \leq H \leq 6$
-   $1 \leq W \leq 10^{12}$

Sample 1 Input

2 2

Sample 1 Output

7
We have the following seven ways:

Sample 2 Input

3 3

Sample 2 Output

131

Sample 3 Input

5 100

Sample 3 Output

379944232

HINT

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