N = int(input())
A = list(map(int,input().split()))
one = sum(A)
zero = N - one
B = []
for i in range(min(one,zero)):
  B.append(0)
  B.append(1)
  one -= 1
  zero -= 1
for i in range(one):
  B.append(1)
for i in range(zero):
  B.append(0)

ans = 0
for i in range(N):
  if B[i] == 1 and B[(i-1) % N] == 0:
    ans += 1

mod = 998244353
ans *= pow(N,mod-2,mod)
ans %= mod
print(ans)