from math import e
import sys, time, random
from collections import deque, Counter, defaultdict
def debug(*x):print('debug:',*x, file=sys.stderr)
input = lambda: sys.stdin.readline().rstrip()
ii = lambda: int(input())
mi = lambda: map(int, input().split())
li = lambda: list(mi())
inf = 2 ** 61 - 1
mod = 998244353

n = ii()

c = li()

if 0 in c:
    z = True
    c.remove(0)
else:
    z = False
    
if len(c) == 0:
    print(1)
    exit()
    
if min(c) > 0 or max(c) < 0:
    ans = pow(2, len(c) - 1, mod)
    ans *= (z + 1)
    ans %= mod
    print(ans)
    exit()
    
    
plus = 0
minus = 0

for v in c:
    if v > 0:
        plus += 1
    else:
        minus += 1
        
#p-m

ans = 2 * pow(2, plus - 1, mod) * pow(2, minus - 1, mod)
if z:
    ans *= 3
    
print(ans % mod)