#include <bits/stdc++.h>
using namespace std;
const int maxn = 25;
int a[maxn], b[maxn], c[maxn];
int main() {
  int n, points = 0, x;
  cin >> n;
  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];
  }
  for (int i = 1; i < n; i++) {
    if (a[i] == a[i - 1] + 1) {
      points = points + (b[i - 1]);
      points = points + c[n - i - 1];
    } else {
      points = points + b[i - 1];
    }
  }
  points = points + b[n - 1];
  cout << points << endl;
}
