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