#include <bits/stdc++.h>
using namespace std;
int n, a[25], b[25], c[25];
long long ans;
int main() {
  scanf("%d", &n);
  a[1] = 25;
  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; i++) {
    cin >> c[i];
  }
  for (int i = 1; i <= n; i++) {
    ans += b[a[i]];
    if (a[i] - 1 == a[i - 1]) {
      ans += c[i - 2];
    }
  }
  cout << ans;
  return 0;
}
