#include <bits/stdc++.h>
using namespace std;
const long long int mod = 1e9 + 7;
const long long int INF = 2e9;
const double epsilon = 1e-7;
const double PI = 3.1415926535;
long long int gcd(long long int a, long long int b) {
  return b ? gcd(b, a % b) : a;
}
int main() {
  int n;
  cin >> n;
  int sum = 0;
  vector<int> a(n), b(n), c(n - 1);
  for (long long int i = 0; i < (long long int)(n); i++) cin >> a[i];
  for (long long int i = 0; i < (long long int)(n); i++) {
    cin >> b[i];
    sum += b[i];
  }
  for (long long int i = 0; i < (long long int)(n - 1); i++) cin >> c[i];
  for (long long int i = 0; i < (long long int)(n - 1); i++) {
    if (a[i + 1] == a[i] + 1) {
      sum += c[a[i]];
    }
  }
  cout << sum << endl;
}
