#include <bits/stdc++.h>
using namespace std;
int n, a[100], b[100], c[100];
int main() {
  cin >> n;
  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];
  int ans = b[a[1]];
  for (int i = 2; i <= n; ++i) {
    ans += b[a[i]];
    if (a[i - 1] + 1 == a[i]) ans += c[a[i]];
  }
  cout << ans << endl;
}
