#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
typedef long long ll;
int main(){
    int n,A[200001],B[200001],C[200001];
    ll ans=0;
    cin>>n;
    rep(i,n) cin>>A[i];
    rep(i,n) cin>>B[i];
    rep(i,n-1) cin>>C[i];
    rep(i,n) ans+=B[A[i]-1];
    rep(i,n-1) if(A[i]+1==A[i+1]) ans+=C[A[i]-1];
    cout<<ans;
}