n = int(input())
A = list(map(int, input().split()))
INF = float('inf')

M = A[0]
m = A[0]
for i in range(1, n):
    a = A[i]
    nM = -INF
    nm = INF
    if a != 0:
        nM = max([M+a, M-a, M*a, M//a, m+a, m-a, m*a, m//a])
        nm = min([M+a, M-a, M*a, M//a, m+a, m-a, m*a, m//a])
    else:
        nM = max([M+a, M-a, M*a, m+a, m-a, m*a])
        nm = min([M+a, M-a, M*a, m+a, m-a, m*a])
    M, m = nM, nm
print(M)