import itertools
N = int(input())
lsa = list(map(int,input().split()))
c = -float('INF')
for p in itertools.product(range(3),repeat=N-1):
    a = lsa[0]
    for i in range(1,N):
        if p[i-1] == 0:
            a += lsa[i]
        elif p[i-1] == 1:
            a *= lsa[i]
        else:
            a -= lsa[i]
    c = max(c,a)
print(c)