#include <bits/stdc++.h>
using namespace std;

#define fi first
#define se second
#define repl(i,a,b) for(int i=(int)(a);i<(int)(b);i++)
#define repr(i,n) for(int i=(int)(n-1);i>=0;i--)
#define rep(i,n) repl(i,0,n)
#define each(itr,v) for(auto itr:v)
#define pb(s) push_back(s)
#define all(x) (x).begin(),(x).end()
#define dbg(x) cout << #x" = " << x << endl
#define print(x) cout << x << endl
#define maxch(x,y) x=max(x,y)
#define minch(x,y) x=min(x,y)
#define uni(x) x.erase(unique(all(x)),x.end())
#define exist(x,y) (find(all(x),y)!=x.end())
#define bcnt(x) bitset<32>(x).count()

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> P;
typedef pair<P, int> PPI;
typedef pair<int, P> PIP;
typedef pair<ll, ll> PL;
typedef pair<P, ll> PPL;

#define INF INT_MAX/3
#define MAX_N 1000000001

int n;
int d[800][800];
bool visited[800];
int maxi, u;
set<int> st;

void dfs(int v, int c) {
    visited[v] = true;

    bool end = true;
    rep(i, n) {
        if (d[v][i] < INF && !visited[i] && !st.count(i)) {
            end = false;
            dfs(i, c + d[v][i]);
        }
    }

    if (end) {
        if (maxi <= c) {
            maxi = c;
            u = v;
        }
    }
}

int main(){
    cin.sync_with_stdio(false);
    while(cin >> n, n) {
        rep(i, n)rep(j, n) d[i][j] = INF;
        st.clear();

        vector<int> p(n);
        int sum = 0;
        repl(i, 1, n) cin >> p[i], p[i]--;
        repl(i, 1, n) {
            int tmp;
            cin >> tmp;
            d[i][p[i]] = d[p[i]][i] = tmp;
            sum += tmp;
        }

        int e = 0, tmp = -1;
        rep(i, n){
            int cnt = 0, len = 0;
            rep(j, n) if (d[i][j] < INF) cnt++, len = d[i][j];
            if (cnt == 1) st.insert(i), e += len;
            else tmp = i;
        }

        if (tmp >= 0) {
            memset(visited, 0, sizeof(visited)), maxi = 0;
            dfs(tmp, 0), tmp = u;
            memset(visited, 0, sizeof(visited)), maxi = 0;
            dfs(tmp, 0);
        } else maxi = 0;

        int ans = maxi * 2 + e + (sum - maxi - e) * 3;
        cout << ans << endl;
    }

    return 0;
}