#include <fstream>
#include <vector>
#include <algorithm>
#define Nmax (1<<14)
using namespace std;
  
vector <int> Arb[Nmax];
long long Sol;
long long N,A[Nmax];
  
bool cmp(int X,int Y) {
    return A[X]>A[Y];
}
void UpDfs(int Nod) {
      
    for(int i=0;i<Arb[Nod].size();i++) {
        UpDfs(Arb[Nod][i]);
        A[Nod]+=A[Arb[Nod][i]];
        }
      
    sort(Arb[Nod].begin(),Arb[Nod].end(),cmp);
      
}
void DownDfs(int Nod) {
      
    for(int i=0;i<Arb[Nod].size();i++) {
        Sol+=1LL*(i+1)*A[Arb[Nod][i]];
        DownDfs(Arb[Nod][i]);
        }
      
}
void Solve() {
      
    UpDfs(1);
    Sol+=A[1];
    DownDfs(1);
      
}
void Read() {
      
    int i,x;
    ifstream in("dosare.in");
    in>>N;
      
    for(i=2;i<=N;i++) {
        in>>x;
        Arb[x].push_back(i);
        }
      
    for(i=1;i<=N;i++)
        in>>A[i];
      
    in.close();
      
}
void Write() {
      
    ofstream out("dosare.out");
    out<<Sol<<'\n';
    out.close();
      
}
int main() {
      
    Read();
    Solve();
    Write();
      
    return 0;
      
}