#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;

int main() {
  ll N, M1, M2; cin >> N;
  cin >> M1;
  vector<ll> A(M1);
  for (int i = 0; i < M1; i++) cin >> A[i];
  cin >> M2;
  vector<ll> B(M2);
  for (int i = 0; i < M2; i++) cin >> B[i];
  vector<bool> f(N + 1, true);
  f[0] = false;
  ll now = 0;
  for (int i = 0; i < M1; i++) {
    now += A[i];
    f[now] = false;
  }
  for (int i = 0; i < M2; i++) {
    now -= B[i];
    f[now] = false;
  }
  ll ans = 0;
  for (int i = 0; i <= N; i++) {
    if (f[i]) ans++;
  }
  cout << ans << endl;
  return 0;
}