#include<bits/stdc++.h>
using namespace std;
const int N = 1e5+5;

int n,a[N],b[N],c[N];
int ans;

int main(){
	cin>>n;
	for(int i=1;i<=n;++i)cin>>a[i];
	for(int i=1;i<=n;++i)cin>>b[i];
	for(int i=1;i<n;++i)cin>>c[i];
	for(int i=1;i<=n;++i){
		ans+=b[a[i]];
		if(i>=2&&a[i-1]+1==a[i])ans+=c[a[i-1]];
	}
	cout<<ans<<endl;
} 