n = int(input())
a = list(map(int, input().split()))
a.sort(reverse=True)

if n == 1:
    print(a[0])
elif n == 2:
    print(a[0] * a[1])
else:
    if (n - 1) % 2 == 0:  # Bob's last move (n is odd)
        print(1)
    else:  # Alice's last move (n is even)
        print(a[0] * a[1])