dlina = int(input())
a = input().split()
b = input().split()
max = 0

for i in range(dlina):
    for j in range(i + 1):
        if i == j:
            pass
        else:
            resultit = int(a[i]) * int(b[j]) + int(a[j]) * int(b[i])
            if resultit > max:
                max = resultit


print(max)