#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, a[100], b[100], c[100] = {};
  int sum = 0;
  cin >> 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];
  }
  int flag = 0;
  for (int i = 0; i < n; i++) {
    sum += b[a[i] - 1];
    if (flag + 1 == a[i] - 1) {
      sum += c[flag];
    }
    flag = a[i] - 1;
  }
  cout << sum << '\n';
  return 0;
}
