Problem Statement
Consider a permutation $P=(P_1,P_2,\cdots,P_{2^N-1})$ of $(1,2,\cdots,2^N-1)$. $P$ is said to be heaplike if and only if all of the following conditions are satisfied.
$P_i < P_{2i}$($1 \leq i \leq 2^{N-1}-1$)$P_i < P_{2i+1}$($1 \leq i \leq 2^{N-1}-1$)
You are given integers $A$ and $B$. Let $U=2^A$ and $V=2^{B+1}-1$.
Find the probability, modulo $998244353$, that $P_U<P_V$ for a heaplike permutation chosen uniformly at random.
Definition of probability modulo $998244353$ It can be proved that the sought probability is always rational. Additionally, under the constraints of this problem, when the sought rational number is represented as an irreducible fraction $\frac{P}{Q}$, it can be proved that $Q \neq 0 \pmod{998244353}$. Therefore, there is a unique integer $R$ such that $R \times Q \equiv P \pmod{998244353}$ and $0 \leq R \lt 998244353$. Print this $R$.
Constraints
$2 \leq N \leq 5000$$1 \leq A,B \leq N-1$- All numbers in the input are integers.
Input
The input is given from Standard Input in the following format:
N A B
Output
Print the answer.
样例
2 1 1
499122177
3 1 2
124780545
4 3 2
260479386
2022 12 25
741532295
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