#include <bits/stdc++.h>
using namespace std;
using in = int64_t;
const double PI = 3.14159265358979323846;
const int64_t waru = 1000000007;
const in INF = 1 << 30;
int main() {
  int n;
  cin >> n;
  vector<int> a(n);
  for (in i = 0; i < (in)(n); i++) cin >> a[i];
  vector<int> b(n);
  for (in i = 0; i < (in)(n); i++) cin >> b[i];
  vector<int> c(n);
  for (in i = 0; i < (in)(n); i++) cin >> c[i];
  int cnt = 0;
  for (in i = 0; i < (in)(n); i++) {
    cnt += b[i];
  }
  for (in i = 0; i < (in)(n - 1); i++) {
    if (a[i] + 1 == a[i + 1]) {
      cnt += c[a[i]];
    }
  }
  cout << cnt;
}
