#include <bits/stdc++.h>
using namespace std;
int main() {
  int N;
  cin >> N;
  int A[20], B[20], C[20];
  for (int i = 0; i < N; i++) cin >> A[i];
  for (int i = 0; i < N; i++) cin >> B[i];
  for (int i = 0; i < N - 1; i++) cin >> C[i];
  int sum = 0;
  int prev = 0;
  for (int i = 0; i < N; i++) {
    sum += B[A[i] - 1];
    if (prev == A[i] - 1) sum += C[prev - 1];
    prev = A[i];
  }
  cout << sum << endl;
}
