// #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll = long long;
#define rep(i,n) for (ll i = 0; i < (n); ++i)
using vl = vector<ll>;
using vvl = vector<vl>;
using P = pair<ll,ll>;
#define pb push_back
#define int long long
#define double long double
#define INF (ll) 3e18
// Ctrl + Shift + B コンパイル
// Ctrl + C 中断
// ./m 実行


signed main(){
  int n; cin >> n;
  int m; cin >> m;
  vl a(m);
  for(auto &x : a) cin >> x;
  cin >> m;
  vl b(m);
  for(auto &x : b) cin >> x;
  vl clean(n+1,1);
  int now = 0;
  for(auto x : a) {
    now += x;
    clean[now] = 0;
  }
  for(auto x : b) {
    now -= x;
    clean[now] = 0;
  }
  int ans = 0;
  for(auto x : clean) ans += x;
  cout << ans << endl;
}