#include <bits/stdc++.h>
using namespace std;
int main() {
  int N;
  cin >> N;
  int a[N];
  for (int i = 0; i < N; ++i) {
    cin >> a[i];
  }
  int b[N];
  for (int i = 0; i < N; ++i) {
    cin >> b[i];
  }
  int c[N];
  for (int i = 0; i < N - 1; ++i) {
    cin >> c[i];
  }
  int point = 0;
  for (int i = 0; i < N; ++i) {
    if (i > 1 && a[i] - 1 == a[i - 1]) {
      point += c[i - 1];
    }
    point += b[i - 1];
  }
  cout << point << endl;
}
