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