#include <bits/stdc++.h>
using namespace std;
int n,a[100],b[100],c[100];
int main() {
  cin>>n; for (int i=1; i<=n; ++i) cin>>a[i];
  for (int i=1; i<=n; ++i) cin>>b[i];
  for (int i=1; i<n; ++i) cin>>c[i];
  int ans=b[a[1]];
  for (int i=2; i<=n; ++i) {
    ans+=b[a[i]];
    if (a[i-1]+1==a[i]) ans+=c[a[i-1]];
  }
  cout<<ans<<endl;
}