N = int(input())
A = list(map(int, input().split()))
m = z = p = 0
for a in A:
    if a < 0:
        m += 1
    if a == 0:
        z += 1
    if a > 0:
        p += 1

mod = 998244353
if m > 0 and p > 0:
    ans = 2 * pow(2, m - 1, mod) * pow(3, z, mod) * pow(2, p - 1, mod) % mod
elif m == 0 and p == 0:
    print(1)
else:
    ans = pow(2, max(0, m - 1), mod) * pow(2, z, mod) * pow(2, max(0, p - 1), mod) % mod
print(ans)