#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using vi = vector<int>;
using vii = vector<vector<int>>;
using viii = vector<vector<vector<int>>>;
using vl = vector<ll>;
using vll = vector<vector<ll>>;
using vlll = vector<vector<vector<ll>>>;
using vc = vector<char>;
using vcc = vector<vector<char>>;
using pi = pair<int, int>;
using pl = pair<ll, ll>;
ll mod = ll(1e9) + 7;
ll inf = ll(1e18);
void bl(bool b, ostream& out = cout) { out << (b ? "Yes" : "No") << endl; }
void bl2(bool b, ostream& out = cout) { out << (b ? "YES" : "NO") << endl; }
template <typename T>
inline bool chmax(T& a, T b) {
  if (a < b) {
    a = b;
    return true;
  }
  return false;
}
template <typename T>
inline bool chmin(T& a, T b) {
  if (a > b) {
    a = b;
    return true;
  }
  return false;
}
int dx[] = {1, 0, -1, 0, 1, -1, 1, -1};
int dy[] = {0, 1, 0, -1, 1, -1, -1, 1};
using namespace std;
namespace dbg {
using ll = long long;
class Debug {
  void prefix(string s) {
    cout << "\033[7m\033[35m"
         << " DEBUG "
         << "\033[0m\033[35m"
         << " " << s << "\033[0m" << endl;
  }

 public:
  Debug() {}
  template <typename T>
  void print(vector<T>& vec);
  template <typename T1, typename T2>
  void print(vector<pair<T1, T2>>& vec, int idx = 0);
  template <typename T>
  void print(vector<vector<T>>& vec);
  template <typename T>
  void print(vector<vector<vector<T>>>& vec);
  template <typename T>
  void print(T* arr, ll n);
  template <typename T>
  void print(T* arr, int n, int m);
  template <typename T>
  void print(set<T>& st);
  template <typename T>
  void print(T cont);
};
template <typename T>
void Debug::print(vector<T>& vec) {
  prefix("vector");
  for (auto& v : vec) cout << v << " ";
  cout << endl;
}
template <typename T1, typename T2>
void Debug::print(vector<pair<T1, T2>>& vec, int idx) {
  prefix("vector pair");
  for (auto& v : vec) cout << (!idx ? get<0>(v) : get<1>(v)) << " ";
  cout << endl;
}
template <typename T>
void Debug::print(vector<vector<T>>& vec) {
  prefix("vector d2");
  for (auto& vv : vec) {
    for (auto& v : vv) cout << v << " ";
    cout << endl;
  }
}
template <typename T>
void Debug::print(vector<vector<vector<T>>>& vec) {
  prefix("vector d3");
  for (auto& vvv : vec) {
    cout << "[";
    for (int i = 0; i < vvv.size(); i++) {
      if (i) cout << " ";
      for (int j = 0; j < vvv[i].size(); j++) {
        if (j) cout << " ";
        cout << vvv[i][j];
      }
      if (i != vvv.size() - 1) cout << endl;
    }
    cout << "]" << endl;
  }
}
template <typename T>
void Debug::print(T* arr, ll n) {
  prefix("array");
  for (int i = 0; i < n; i++) cout << arr[i] << " ";
  cout << endl;
}
template <typename T>
void Debug::print(T* arr, int n, int m) {
  prefix("array d2");
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      cout << arr[i][j] << " ";
    }
    cout << endl;
  }
}
template <typename T>
void Debug::print(set<T>& st) {
  prefix("set");
  for (auto& e : st) cout << e << " ";
  cout << endl;
}
template <typename T>
void Debug::print(T cont) {
  prefix("key value");
  for (auto& e : cont) cout << e.first << " : " << e.second << endl;
  cout << endl;
}
}  // namespace dbg
dbg::Debug debug;
class BBuffet {
 public:
  void solve(std::istream& in, std::ostream& out) {
    int n;
    vi a(n), b(n), c(n - 1);
    in >> n;
    for (int i = 0; i < n; i++) in >> a[i];
    for (int i = 0; i < n; i++) in >> b[i];
    for (int i = 0; i < n - 1; i++) in >> c[i];
    ll res = 0;
    for (int i = 0; i < n; i++) {
      res += b[i];
      if (i < n - 1 && a[i + 1] == a[i] + 1) res += c[a[i] - 1];
    }
    out << res << "\n";
  }
};
int main() {
  cin.tie(nullptr);
  ios_base::sync_with_stdio(false);
  BBuffet solver;
  std::istream& in(std::cin);
  std::ostream& out(std::cout);
  solver.solve(in, out);
  return 0;
}
