#include <bits/stdc++.h>
using namespace std;
int n;
int A[20];
int B[20];
int C[20];
int main() {
  int fll = 0;
  cin >> n;
  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 - 1; i++) {
    cin >> C[i];
  }
  int rmd = -50;
  for (int i = 1; i <= n; i++) {
    fll += B[A[i]];
    if (A[i] == rmd + 1) {
      fll += C[rmd];
    }
    rmd = A[i];
  }
  cout << fll << "\n";
  return 0;
}
