#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
typedef long long ll;
#define _GLIBCXX_DEBUG
typedef vector<int> vec;
typedef vector<ll> lvec;
typedef vector<char>cvec;
typedef pair<ll, ll> LP;
typedef tuple<ll, ll, ll> LT;
typedef pair<int, int> P;
typedef tuple<int, int, int> T;
int main()	{
  int n,sum=0;
  cin>>n;
  vector<int> a(n),b(n),c(n-1);
  rep(i,n) {
    cin>>a[i];
    a[i]--;
  }
  rep(i,n) cin>>b[i];
  rep(i,n-1) cin>>c[i];
  rep(i,n){
    sum+=b[a[i]];
    if(i>0 && a[i-1]+1=a[i])
      sum+=c[a[i-1]];
  }
  cout<<sum<<endl;
}