MOD = 1000000007

n = gets.to_i
xs = (0..n).map{gets.to_i}
ys = (0..n).map{gets.to_i}
ys_acc = [0] * (n+1)
(n+1).times {|i| ys_acc[i+1] = ys_acc[i] + ys[i] }
p (0..n).map{|i| xs[i] * ys_acc[n-i+1] % MOD}.inject(:+) % MOD