n = int(input())
a = list(map(int,input().split()))
a.sort()
if n == 1:
    print(a[0])
elif n % 2:
    print(a[0] * a[1])
elif n % 2:
    #bobの手番で終わる
    print(1)
else:
    print(a[0] * a[1])