#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
using namespace std;
template <typename Arg1>
void __f(const char* name, Arg1&& arg1) {
  cerr << name << " : " << arg1 << std::endl;
}
template <typename Arg1, typename... Args>
void __f(const char* names, Arg1&& arg1, Args&&... args) {
  const char* comma = strchr(names + 1, ',');
  cerr.write(names, comma - names) << " : " << arg1 << " | ";
  __f(comma + 1, args...);
}
const int maxN = 100100;
void solve() {
  long long n;
  cin >> n;
  long long a[n], b[n], c[n], sum = 0;
  for (long long i = 0; i < (n); ++i) cin >> a[i];
  for (long long i = 0; i < (n); ++i) cin >> b[i], sum += b[i];
  for (long long i = 0; i < (n - 1); ++i) {
    cin >> c[i];
    if (a[i] + 1 == a[i + 1]) sum += c[a[i] - 1];
  }
  cout << sum << endl;
}
int main() {
  cin.sync_with_stdio(0);
  cin.tie(0);
  cin.exceptions(cin.failbit);
  solve();
  return 0;
}
