#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  vector<int> a;
  vector<int> b;
  vector<int> c;
  int sum = 0;
  for (long long i = 0; i < (n); i++) {
    int tmp;
    cin >> tmp;
    a.push_back(tmp);
  }
  for (long long i = 0; i < (n); i++) {
    int tmp;
    cin >> tmp;
    b.push_back(tmp);
    sum += tmp;
  }
  for (long long i = 0; i < (n - 1); i++) {
    int tmp;
    cin >> tmp;
    c.push_back(tmp);
  }
  for (long long i = 0; i < (n - 1); i++) {
    if (a[i + 1] - 1 == a[i]) {
      sum += c[a[i] - 1];
    }
  }
  cout << sum << endl;
  return 0;
}
