#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
using ll=long long;

void IO(){
  ios::sync_with_stdio(false);
  std::cin.tie(nullptr);
}

int main(){
  IO();
  ll n;
  cin>>n;
  ll m1;
  cin>>m1;
  vector<bool> isd(n+1,false);
  isd[0]=true;
  ll now=0;
  for(ll i=0;i<m1;i++){
    ll a;
    cin>>a;
    now+=a;
    isd[now]=true;
  }
  ll m2;
  cin>>m2;
  for(ll i=0;i<m2;i++){
    ll b;
    cin>>b;
    now-=b;
    isd[now]=true;
  }
  ll ans=n+1;
  for(ll i=0;i<=n;i++){
    if(isd[i]){
      ans--;
    }
  }
  cout<<ans<<endl;
}