#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int n;
  cin >> n;
  vector<int> a(n);
  vector<int> b(n);
  vector<int> c(n - 1);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
    --a[i];
  }
  for (int i = 0; i < n; ++i) {
    cin >> b[i];
  }
  for (int i = 0; i < n; ++i) {
    cin >> c[i];
  }
  int sum = 0;
  for (int i = 0; i < n; ++i) {
    sum += b[a[i]];
    if (i > 0 && a[i] == a[i - 1] + 1) sum += c[a[i]];
  }
  cout << sum << endl;
  return 0;
}
