#include <iostream>
using namespace std;

int main(){
	int n;
	cin >> n;
	int a[n],b[n],c[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];
	int sum = b[a[0]-1];
	for(int i = 1;i<n;i++){
		sum += b[a[i]-1];
		if(a[i] - a[i-1] == 1)sum+=c[a[i-1]-1];
	}
	cout << sum << endl;
}