N =int(input())
A = list(map(int,input().split()))
A.sort()
if N==1:
    out = A[0]
elif N==2:
    out = A[0] * A[1]
else:
    if N%2 == 0:
        out = max(A[2], A[0]*A[1])
    else:
        out = 1

print(out)