#include<stdio.h>
int v[200005];
int a[200005], b[200005];
int main()
{
	int n;
	scanf("%d", &n);
	int i, j;
	int m1, m2;
	scanf("%d", &m1);
	for (i = 0; i < m1; i++)
		scanf("%d", &a[i]);
	scanf("%d", &m2);
	for (i = 0; i < m2; i++)
		scanf("%d", &b[i]);
	for (i = 0; i <= n; i++)
		v[i] = 1;
	j = 0;
	for (i = 0; i < m1; i++)
	{
		j += a[i];
		v[j] = 0;
	}
	for (i = 0; i < m2; i++)
	{
		j -= b[i];
		v[j] = 0;
	}
	int ans = 0;
	for (i = 0; i <= n; i++)
		ans += v[i];
	printf("%d\n", ans);
	return 0;
}