import sys
sys.setrecursionlimit(5*10**5)
input = sys.stdin.readline
from collections import defaultdict, deque, Counter
from heapq import heappop, heappush
from bisect import bisect_left, bisect_right
from math import gcd

n = int(input())
m1 = int(input())
a = list(map(int,input().split()))
m2= int(input())
b = list(map(int,input().split()))
now = 0
dirty = set()
for i in range(m1):
    now += a[i]
    dirty.add(now)

for i in range(m2):
    now -= b[i]
    dirty.add(now)
print(n+1-len(dirty))