n=int(input())+1
a=[int(input()) for _ in range(n)]
b=[int(input()) for _ in range(n)]
res=[0]*n
res[0]=a[0]
for i in range(1,n):
    res[i]=res[i-1]+a[i]
print(sum(i*j for i,j in zip(res[::-1],b))%(10**9+7))