arbsum

#include <cstdio>
#include <algorithm>
#include <vector>
#define N 100001
using namespace std;
int n,x,i,v[N],A[N],B[N];
vector<int> V[N];

void DF(int nod)
{
    A[nod]=0;
    B[nod]=v[nod];
    if(V[nod].size()==0)
        return;
    for(vector<int>::iterator it=V[nod].begin();it!=V[nod].end();++it)
        DF(*it);
    for(vector<int>::iterator it=V[nod].begin();it!=V[nod].end();++it)
        A[nod]+=max(A[*it],B[*it]),B[nod]+=A[*it];
}

int main()
{
    scanf("%d %d",&n,&x);
    for(i=2;i<=n;++i)
        scanf("%d",&x),V[x].push_back(i);
    for(i=1;i<=n;++i)
        scanf("%d",&v[i]);
    DF(1);
    printf("%d\n",max(A[1],B[1]));
    return 0;
}