#include <bits/stdc++.h>
using namespace std;
int main(void) {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  int N = 0;
  cin >> N;
  vector<int> A(N), B(N), C(N - 1);
  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];
  int total = 0;
  for (int i = 0; i < N; i++) {
    int manzoku = B[A[i] - 1];
    int sub = 0;
    if (i < N - 1) {
      sub = (A[i + 1]) - (A[i]);
    }
    int tuika = ((int)abs(sub) == 1) ? C[A[i] - 1] : 0;
    total += manzoku + tuika;
  }
  cout << total;
  return 0;
}
