#include <bits/stdc++.h>
using namespace std;

int main() {
  int n;
  cin >> n;
  vector<bool> dirty(n + 1, false);
  dirty[0] = true;
  int m;
  cin >> m;
  int cur = 0;
  for (int i = 0; i < m; i++) {
    int a;
    cin >> a;
    cur += a;
    dirty[cur] = true;
  }

  cin >> m;
  for (int i = 0; i < m; i++) {
    int b;
    cin >> b;
    cur -= b;
    dirty[cur] = true;
  }

  int ans = 0;
  for (const auto &d : dirty) {
    ans += !d;
  }
  cout << ans << '\n';
  return 0;
}