def main():
	n=int(input())
	m1=int(input())
	a=list(map(int,input().split()))
	m2=int(input())
	b=list(map(int,input().split()))
	
	d=set()
	c = 0
	for i in range(m1):
		c += a[i]
		d.add(c)
	c = n
	for i in range(m2):
		c -= b[i]
		d.add(c)
	ans = n - len(d)
	print(ans+1)
	
if __name__ == "__main__":
	main()