#include<iostream>
using namespace std;
int main(){
  int n,i,ans,b;cin >> n;
  ans = 0;
  int a[n];
  for (i=0;i<n;i++) cin >> a[i];
  for (i=0;i<n;i++){
    cin >> b;
    ans += b;
  }
  int c[n-1];
  for (i=0;i<n-1;i++) cin >> c[i];
  for (i=1;i<n;i++){
    if (a[i]-1 == a[i-1]){
      ans += c[a[i]-2];
    }
  }
  cout << ans << endl;  
}
  