# coding: utf-8
# Your code here!

N=int(input())

M1=int(input())
A=list(map(int,input().split()))

M2=int(input())
B=list(map(int,input().split()))

stairs=[1]*(N+1)
stairs[0]=0

now=0
for a in A:
    now+=a
    stairs[now]=0
    
for b in B:
    now-=b
    stairs[now]=0
    

print(sum(stairs))