10368: ABC327 —— G - Many Good Tuple Problems
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Description
> The definition of a good pair of sequences in this problem is the same as in Problem D.
A pair of sequences of length $M$ consisting of positive integers at most $N$, $(S, T) = ((S_1, S_2, \dots, S_M), (T_1, T_2, \dots, T_M))$, is said to be a good pair of sequences when $(S, T)$ satisfies the following condition.
- There exists a sequence $X = (X_1, X_2, \dots, X_N)$ of length $N$ consisting of $0$ and $1$ that satisfies the following condition:
- $X_{S_i} \neq X_{T_i}$ for each $i=1, 2, \dots, M$.
Among the $N^{2M}$ possible pairs of sequences of length $M$ consisting of positive integers at most $N$, $(A, B) = ((A_1, A_2, \dots, A_M), (B_1, B_2, \dots, B_M))$, find the number, modulo $998244353$, of those that are good pairs of sequences.
A pair of sequences of length $M$ consisting of positive integers at most $N$, $(S, T) = ((S_1, S_2, \dots, S_M), (T_1, T_2, \dots, T_M))$, is said to be a good pair of sequences when $(S, T)$ satisfies the following condition.
- There exists a sequence $X = (X_1, X_2, \dots, X_N)$ of length $N$ consisting of $0$ and $1$ that satisfies the following condition:
- $X_{S_i} \neq X_{T_i}$ for each $i=1, 2, \dots, M$.
Among the $N^{2M}$ possible pairs of sequences of length $M$ consisting of positive integers at most $N$, $(A, B) = ((A_1, A_2, \dots, A_M), (B_1, B_2, \dots, B_M))$, find the number, modulo $998244353$, of those that are good pairs of sequences.
Input
The input is given from Standard Input in the following format:
```
$N$ $M$
```
```
$N$ $M$
```
Output
Print the number, modulo $998244353$, of pairs of sequences of length $M$ consisting of positive integers at most $N$ that are good pairs of sequences.
Constraints
- $1 \leq N \leq 30$
- $1 \leq M \leq 10^9$
- $N$ and $M$ are integers.
- $1 \leq M \leq 10^9$
- $N$ and $M$ are integers.
Sample 1 Input
3 2
Sample 1 Output
36
For example, if A=(1,2),B=(2,3), then (A,B) is a good pair of sequences. Indeed, if we set X=(0,1,0), then X is a sequence of length N consisting of 0 and 1 that satisfies $X_{A_1}≠X_{B_1}$ and $X_{A_2}≠X_{B_2}$. Thus, (A,B) satisfies the condition of being a good pair of sequences.
There are a total of 36 good pairs of sequences, so print this number.
There are a total of 36 good pairs of sequences, so print this number.
Sample 2 Input
3 3
Sample 2 Output
168
Sample 3 Input
12 34
Sample 3 Output
539029838