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