using System;

namespace ABC140B
{
    class Program
    {
        static void Main(string[] args)
        {
            int aa = int.Parse(Console.ReadLine());
            int[] b = new int[aa+1];
            int[] c = new int[aa];
            int v = 0;
            int x = 0;
            var a = Console.ReadLine().Split(' ');
            var ab = Console.ReadLine().Split(' ');
            var ac = Console.ReadLine().Split(' ');
            int n =int.Parse( a [aa - 1]);

            for (int i = 1;i <= aa;i++)
            {
                b[i] = int.Parse(ab[i-1]);
                x += b[i];
            }
            for (int i = 1; i <= aa - 1; i++)
            {
                c[i] = int.Parse(ac[i-1]);
               
            }
            v = c[n - 1];
            x += v;
            Console.WriteLine(x);
        }
    }
}
