N = int(input())
A = []
for i in range(N + 1):
    A.append(int(input()))
S = sum(A)   
    
ans = 0
mod = 10 ** 9 + 7
for i in range(N + 1):
    ans += S * int(input())
    ans %= mod
    S -= A.pop()
    
print(ans)