using System.Linq;
using System;

public class Hello
{
    static void Main()
    {
        var n = int.Parse(Console.ReadLine().Trim());
        var an = int.Parse(Console.ReadLine().Trim());
        string[] line = Console.ReadLine().Trim().Split(' ');
        var a = Array.ConvertAll(line, int.Parse);
        var bn = int.Parse(Console.ReadLine().Trim());
        line = Console.ReadLine().Trim().Split(' ');
        var b = Array.ConvertAll(line, int.Parse);
        getAns(n, an, a, bn, b);
    }
    static void calc(int n, int aL, int[] a, bool[] c)
    {
        var p = 0;
        c[p] = true;
        for (int i = 0; i < aL; i++)
        {
            p += a[i];
            c[p] = true;
        }
    }
    static void getAns(int n, int an, int[] a, int bn, int[] b)
    {
        var c = new bool[n + 1];
        calc(n, an, a, c);
        Array.Reverse(b);
        calc(n, bn, b, c);
        var ans = c.Count(x => x == false);
        Console.WriteLine(ans);
    }
}