n, a, b = 3, 1, 1
M = 2 * 10**5 + 10
facs = [1] * M
mod = 998244353

for i in range(1, M):
    facs[i] = facs[i - 1] * i
    facs[i] %= mod

if a != b:
    res = facs[n - 1] + (n - 2) * (n - 2) * facs[n - 2]
else:
    res = (n - 1) * (n - 2) * facs[n - 2]

res %= mod
print(res)