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