#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using p = pair<int, int>;
using Graph = vector<vector<int>>;
int main(int argc, const char* argv[]) {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int n;
  cin >> n;
  int a[n], b[n], c[n], ans = 0;
  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++) {
    ans += b[a[i] - 1];
    if (a[i + 1] - 1 == a[i]) ans += c[i - 1];
  }
  cout << ans << endl;
  return 0;
}
