#include <bits/stdc++.h>
using namespace std;
template <class T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
using P = pair<long long, long long>;
long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }
long long lcm(long long a, long long b) { return a * b / gcd(a, b); }
const long long dx[4] = {1, 0, -1, 0};
const long long dy[4] = {0, 1, 0, -1};
const long long INF = 1e12;
const long long MOD = 1e9 + 7;
signed main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(15);
  long long n;
  cin >> n;
  vector<long long> a(n), b(n), c(n - 1);
  for (long long i = 0; i < (long long)n; i++) cin >> a[i];
  for (long long i = 0; i < (long long)n; i++) cin >> b[i];
  for (long long i = 0; i < (long long)n - 1; i++) cin >> c[i];
  long long res = 0;
  for (long long i = 0; i < (long long)n; i++) {
    res += b[a[i] - 1];
    if (i != n - 1 && abs(a[i] - a[i + 1]) == 1) res += c[a[i] - 1];
  }
  cout << res << endl;
}
