n=int(input())
a=[]
b_s=[0]
for i in range(n+1):
  a.append(int(input()))
for i in range(n+1):
  v=int(input())
  b_s.append(b_s[-1]+v)

ans=0
mod=10**9+7
for i in range(n+1):
  ans+=a[n-i]*b_s[i+1]
  ans%=mod
print(ans)