#include <bits/stdc++.h>
using namespace std;
long long int gcd(long long int a, long long int b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
long long int combination(long long int n, long long int k) {
  long long int spaceOptimize[k + 1];
  memset(spaceOptimize, 0, sizeof(spaceOptimize));
  spaceOptimize[0] = 1;
  for (long long int i = 1; i <= n; i++) {
    for (long long int j = min(i, k); j > 0; j--) {
      spaceOptimize[j] = spaceOptimize[j] + spaceOptimize[j - 1];
    }
  }
  return spaceOptimize[k];
}
long long int count_permutation(long long int arr[], long long int n) {
  long long int a[n];
  for (long long int i = 0; i < n; i++) {
    a[i] = i + 1;
  }
  long long int count = 0;
  do {
    count++;
    if (equal(a, a + n, arr)) {
      return count;
    }
  } while (next_permutation(a, a + n));
  return 0;
}
signed main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long int n;
  cin >> n;
  long long int a[n], b[n], c[n - 1];
  for (long long int i = 0; i < n; i++) {
    cin >> a[i];
    a[i]--;
  }
  for (long long int i = 0; i < n; i++) {
    cin >> b[i];
  }
  for (long long int i = 0; i < n - 1; i++) {
    cin >> c[i];
  }
  set<long long int> allReady;
  long long int ans = b[a[0]];
  allReady.insert(a[0]);
  for (long long int i = 1; i < n; i++) {
    ans += b[a[i]];
    if (allReady.find(a[i] - 1) != allReady.end()) {
      ans += c[a[i - 1]];
    }
    allReady.insert(a[i]);
  }
  cout << ans;
  return 0;
}
