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