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