#include<iostream>
using namespace std;
int sum=0;
  int main()
{int n;
 int a[n];
 int b[n],c[n-1];
 cin>>n;
 cout<<"\n";
 for (int i=0;i<n;i++)
   cin>>a[i];
 for (int i=0;i<n;i++)
   cin>>b[i];
 for (int i=0;i<n-1;i++)
   cin>>c[i];

 for (int i=0;i<n;i++)
 {  
    sum=sum+b[i];
 } 
 for (int i=1;i<n;i++)
   { if (a[i-1]+1==a[i])
      sum=sum+c[a[i-1]-1];
   
   else 
     continue;
 
 }
 
 
 cout<<sum;
 
 
 return 0;
 