import math

mod = 998244353

n, a, b = map(int, input().split())

N = math.factorial(n)
AB = math.factorial(n-1)
AABB = math.factorial(n-2)

if a == b:
    result = N - AB * 2
    print(result%mod)
if a != b:
    result = N - AB * 2 + AABB
    print(result%mod)