#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int arr[n];
  int brr[n];
  int crr[n - 1];
  for (int i = 0; i < n; i++) cin >> arr[i];
  int total = 0;
  for (int i = 0; i < n; i++) {
    int aa;
    cin >> aa;
    total += aa;
  }
  for (int i = 0; i < n - 1; i++) {
    cin >> crr[i];
  }
  for (int i = 1; i < n; i++) {
    if (arr[i] == arr[i - 1] + 1) total += crr[arr[i - 1]];
  }
  cout << total << '\n';
}
