#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
const long long INFL = 0x3f3f3f3f3f3f3f3f;
const int MOD = 1e9 + 7;
const double pi = 3.141592653;
using namespace std;
template <class T>
void tomax(T& a, T b) {
  a = max(a, b);
}
template <class T>
void tomin(T& a, T b) {
  a = min(a, b);
}
int main() {
  int n, a[30], b[30], c[30], sum = 0;
  cin >> n;
  for (int i = 1; i <= n; i++) cin >> a[i];
  for (int i = 1; i <= n; i++) cin >> b[i], sum += b[i];
  for (int i = 1; i <= n - 1; i++) cin >> c[i];
  for (int i = 2; i < n; i++) {
    if (a[i] == a[i - 1] + 1) sum += c[a[i - 1]];
  }
  cout << sum << endl;
}
