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