n = int(input()) + 1
a_l = [0]
for i in range(n):
    ai = int(input())
    a_l.append(a_l[-1] + ai)

ans = 0
for i in range(n):
    bi = int(input())
    ans +=  bi * (a_l[n - i])


print(ans % (10**9 + 7))