#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
using namespace std;

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