#include <iostream>
#include <algorithm>
using namespace std;
int main(void){
  int n,i,a[30],b[30],c[30],ans=0;
  cin >> n;
  for (i=0;i<n;i++) cin >> a[i];
  for (i=0;i<n;i++) cin >> b[i];
  for (i=0;i<n-1;i++) cin >> c[i];
  for (i=0;i<n;i++){
    ans+=b[i];
    if (i<n-1 && a[i+1]-a[i]==1) ans+=c[a[i]-1];
  }
  cout << ans << endl;
  return 0;
}