#include <bits/stdc++.h>
using namespace std;
const int INF = 1000000001;
const float PI = 3.14;
typedef map<string, int> msi;
typedef vector<pair<int, int> > vii;
typedef priority_queue<pair<int, int>, vector<pair<int, int> >,
                       greater<pair<int, int> > >
    pq;
list<int>::iterator it;
list<int>::iterator it1;
vector<int>::iterator it2;
vector<int>::iterator it3;
set<int>::iterator it4;
map<string, int>::iterator it5;
vector<pair<int, int> >::iterator iter;
int main(int argc, char* argv[]) {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n;
  cin >> n;
  int A[100];
  int B[100];
  int C[100];
  for (int i = 0; i <= n; i++) {
    A[i] = 0;
    B[i] = 0;
    C[i] = 0;
  }
  for (int i = 1; i <= n; i++) {
    cin >> A[i];
  }
  for (int i = 1; i <= n; i++) {
    cin >> B[i];
  }
  for (int i = 1; i < n; i++) {
    cin >> C[i];
  }
  int suma = 0;
  for (int i = 1; i <= n; i++) {
    if (i == 1)
      suma += B[A[i]];
    else
      suma += B[A[i]] + C[A[i - 1]];
  }
  cout << suma << endl;
  return 0;
}
