#include <iostream>
#define rep(i,N) for(int i=0;i<N;i++)
using namespace std;
int main()
{
	int s=0,n;
	cin >> n;
	int a[n],b[n],c[n];
	rep(i,n) cin >> a[i];
	rep(i,n) cin >> b[i];
	rep(i,n-1) cin >> c[i];
	rep(i,n) s+=b[i];
	rep(i,n-1)
	{
		if((a[i]+1) == (a[i+1]))
			s+=c[a[i]-1];
	}
	cout << s<< endl;
}
