mod = 10**9+7
n = int(input())
a = [None]*(n+1)
b = [None]*(n+1)
for i in range(n+1):
    a[i] = int(input())
for i in range(n+1):
    b[i] = int(input())

ans = 0
sumb = sum(b)
for i in range(1,n+2):
    ans += a[i-1]*sumb%mod
    sumb -= b[-i]

print(ans%mod)