#include<iostream>
using namespace std;
short a[21],b[21],c[20];
int main()
{
	short n,i;
	cin>>n;
	for(i=1;i<=n;++i)
		cin>>a[i];
	for(i=1;i<=n;++i)
		cin>>b[i];
	for(i=1;i<n;++i)
		cin>>c[i];
	int ans=0;
	for(i=1;i<=n;ans+=b[a[i]]+c[(a[i]-1)*(a[i]-a[i-1]==1)],++i);
	cout<<ans;
}