#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n;
  cin >> n;
  long long int a[n], b[n], c[n - 1];
  for (long long int i = 0; i < n; ++i) {
    cin >> a[i];
  }
  for (long long int i = 0; i < n; ++i) {
    cin >> b[i];
  }
  for (long long int i = 0; i < n - 1; ++i) {
    cin >> c[i];
  }
  long long int ans = 0;
  long long int num;
  long long int flag = 1e3;
  long long int plus = 1e3;
  for (long long int i = 0; i < n; ++i) {
    num = a[i];
    ans += b[num - 1];
    if (num == flag + 1) {
      ans += plus;
    }
    if (a[i] < n) {
      flag = a[i];
      plus = c[flag - 1];
    }
  }
  cout << ans << endl;
  return 0;
}
