#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1e9 + 7;
const long long MOD2 = 998244353;
const long long N = 2e5 + 5;
const long double pi = 3.14159265359;
void SRAND() {
  auto duration = std::chrono::system_clock::now().time_since_epoch();
  auto millis =
      std::chrono::duration_cast<std::chrono::milliseconds>(duration).count();
  srand(millis);
}
long long n, a[N], x, c[N], ans, cnt[N];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  for (long long i = 0; i < n; i++) {
    cin >> a[i];
  }
  for (long long i = 0; i < n; i++) {
    cin >> x;
    ans += x;
  }
  for (long long i = 0; i < n - 1; i++) {
    cin >> c[i];
  }
  for (long long i = n - 1; i >= 0; i--) {
    if (cnt[a[i] + 1] == 1) ans += c[a[i] - 1];
    cnt[a[i]] = 1;
  }
  cout << ans << "\n";
  return 0;
}
