input()
ls = [int(x) for x in input().strip().split()]
min_ = ls[0]
max_ = ls[0]

def sign(x):
    return x >= 0

def div(lhs, rhs):
    if sign(lhs) == sign(rhs):
        return abs(lhs) // abs(rhs)
    else:
        return - (abs(lhs) // abs(rhs))

for x in ls[1:]:
    cand = [
        min_ + x,
        max_ + x,
        min_ - x,
        max_ - x,
        min_ * x,
        max_ * x,
    ]
    if x != 0:
        cand.append(div(min_, x))
        cand.append(div(max_, x))
    min_ = min(cand)
    max_ = max(cand)
print(max_)