n = int(input())
pos = []
neg = []
mod = 998244353
zero = False
a = list(map(int, input().split()))
for i in a:
    if i > 0:
        pos.append(i)
    elif i < 0:
        neg.append(i)
    else:
        zero = True
ans = pow(2, len(pos)-1, mod)*pow(2, len(neg)-1, mod)*2 % mod
if zero:
    ans *= 3
print(ans % mod)