# include <stdio.h>
# include <vector>
# include <algorithm>

using namespace std;

# define FIN "dosare.in"
# define FOUT "dosare.out"
# define MAXN 16010
# define MAXM 1000000
# define ll long long

ll N,i,len,x,s;
ll A[MAXN];
ll P[MAXN];
ll ss[MAXM];
vector <ll> dosare[MAXN];   

    int main()
    {
        freopen(FIN,"r",stdin);
        freopen(FOUT,"w",stdout);
        
        scanf("%lld",&N);
        
        for (i = 0; i <= N; ++i) ss[i] = 0;
        
        for (i = 2; i <= N; ++i)
          {
               scanf("%lld",&x);
               dosare[x].push_back(i);
               ss[x] = 1;
          }
        dosare[0].push_back(1);
        ss[0] = 1;
          
        for (i = 1; i <= N; ++i)
          scanf("%lld",&A[i]);
        
        ll j;  
        s = 0;
        for (i = MAXM; i >= 0; --i)
          if (ss[i] == 1)
            {
                len = dosare[i].size();
                for (j = 0; j < len; ++j)
                  P[j + 1] = A [dosare[i][j]];
                  
                sort(P+1,P+len+1);
                
                for (j = len; j >= 1; j--)
                  {
                      A[i] += P[j];
                      s += (len - j + 1) * P[j]; 
                  }       
            }
                        
        printf("%lld",s);
                  
        return 0;
    }