n = int(input())

a = [int(input()) for i in range(n+1)]
b = [int(input()) for i in range(n+1)]

mod = 10**9+7
total = 0

a_sum = sum(a)
for i in range(n, -1, -1):
    total = (total + a_sum*b[n-i]) % mod
    a_sum -= a[i]

print(total)