# 包除原理だな
# if A!=B, total - (N-1)!*2 + (N-2)!
# if A==B, (N-2)*(N-1)!

N, A, B = map(int, input().split())
mod = 998244353

# nCrメモ化パッケージ
factorial = [1] #0分
inverse = [1] #0分
for i in range(1, N+1):
    factorial.append(factorial[-1]*i%mod)
    inverse.append(pow(factorial[-1], mod-2, mod))
    
def nCr_fast(N, R, MOD):
    if N < R or R < 0:
        return 0
    elif R == 0 or R == N:
        return 1
    return factorial[N]*inverse[R]*inverse[N-R]%MOD

if A!=B:
    ans = factorial[N]
    ans -= factorial[N-1]*2
    ans += factorial[N-2]
    ans %= mod
elif A==B:
    ans = (N-2)*factorial[N-1]
    ans %= mod
print(ans)