n = int(input())
m1 = int(input())
A = list(map(int, input().split()))
m2 = int(input())
B = list(map(int, input().split()))

r = [1 for i in range(n+1)]
t = 0

for i in range(m1):
    t += A[i]
    r[t] = 0

for i in range(m2):
    t -= B[i]
    r[t] = 0

print(sum(r))