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


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