mod =10**9 +7
n = int(input())+1
alist =[int(input()) for i in range(n)]
blist =[int(input()) for i in range(n)]

asum=0
sum =0

for i in range(n):
    asum += alist[i]
    sum += asum*blist[n-i-1]
    
print(sum % mod)