import sys
#sys.setrecursionlimit(10 ** 6)
INF = float('inf')
MOD = 10**9 + 7
MOD2 = 998244353
from collections import defaultdict
def ceil(A,B):
    return -(-A//B)
def solve():
    def II(): return int(sys.stdin.readline())
    def LI(): return list(map(int, sys.stdin.readline().split()))
    def LC(): return list(sys.stdin.readline().rstrip())
    def IC(): return [int(c) for c in sys.stdin.readline().rstrip()]
    def MI(): return map(int, sys.stdin.readline().split())
    N = II()
    M1 = II()
    A = LI()
    M2 = II()
    B = LI()
    C = [1]*(N+1)
    C[0] = 0
    C[N] = 0
    a = 0
    for i in range(M1):
      a+=A[i]
      C[a] = 0
    b = 0
    for i in range(M2):
      b+=B[i]
      C[N-b] = 0
    print(sum(C))
    return
solve()