#include <bits/stdc++.h>
using namespace std;
long long int a[100], b[100], c[100], sum = 0, n;
int main() {
  std::ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  for (int i = 0; i < n; i++) {
    cin >> b[i];
    sum = sum + b[i];
  }
  for (int i = 0; i < n - 1; i++) {
    cin >> c[i];
    sum = sum + c[i];
  }
  cout << sum << endl;
  return 0;
}
