using System;

class Program
{
    static void Main()
    {
        int n = int.Parse(Console.ReadLine()) + 1;

        ulong[] a = new ulong[n];
        ulong[] b = new ulong[n];
        ulong bAccumulation = 0;
        ulong Remainder = 1000000007;

        for (int i = 0; i < n; i++)
        {
            b[i] = ulong.Parse(Console.ReadLine());
            bAccumulation += b[i];
            bAccumulation %= Remainder;
        }

        for (int i = 0; i < n; i++)
        {
            a[i] = ulong.Parse(Console.ReadLine());
        }

        ulong Sum = 0;

        for(int i = 0; i < n; i++)
        {
            Sum += a[i] * bAccumulation;

            Sum %= Remainder;
            if (bAccumulation < b[b.Length - i - 1])
            {
                bAccumulation += Remainder;
                bAccumulation -= b[b.Length - i - 1];
            }
            else
            {
                bAccumulation -= b[b.Length - i - 1];
            }

        }

        Console.WriteLine(Sum);
    }
}