#include <bits/stdc++.h>
using namespace std;
int main() {
  int N, count = 0;
  cin >> N;
  vector<int> a(N);
  vector<int> b(N);
  vector<int> c(N);
  for (int i = 0; i < N; i++) {
    cin >> a[i];
  };
  for (int i = 0; i < N; i++) {
    cin >> b[i];
  };
  for (int i = 0; i < N - 1; i++) {
    cin >> c[i];
  }
  c[N - 1] = 0;
  for (int i = 0; i < N; i++) {
    if (a[i] == a[i - 1] + 1)
      count += (b[i] + c[i - 1]);
    else {
      count += b[i];
    }
  };
  cout << count << endl;
}
