#include<iostream>
#include<cstring>
#include<vector>
#include<set>
using namespace std;
using LL = long long;
const int maxn = 2e5 + 5;
vector<int> g[maxn];
int v[maxn], len[maxn];
multiset<int> s[maxn];

void dfs1(int u){
    for(auto &j : g[u]){
        dfs1(j);
        len[u] = max(len[u], len[j] + 1);
        if (len[j] > len[g[u][0]]) swap(j, g[u][0]);
    }
}

void dfs2(int u){
    if (g[u].empty()){
        s[u].insert(v[u]);
        return;
    }
    dfs2(g[u][0]);
    s[u].swap(s[g[u][0]]);
    for(int i = 1; i < g[u].size(); i++){
        int j = g[u][i];
        dfs2(j);
        vector<int> p;
        while(!s[j].empty()){
            p.push_back(max(*prev(s[u].end()), *prev(s[j].end())));
            s[u].erase(prev(s[u].end()));
            s[j].erase(prev(s[j].end()));
        }
        for(auto x : p) s[u].insert(x);
    }
    s[u].insert(v[u]);
    // cout << u << ":\n";
    // for(auto x : s[u]) cout << x << ' ';
    // cout << '\n';
}

int main(){

#ifdef LOCAL
    freopen("data.in", "r", stdin);
    freopen("data.out", "w", stdout);
#endif

    cin.tie(0);
    cout.tie(0);
    ios::sync_with_stdio(0);

    int n;
    cin >> n;
    for(int i = 1; i <= n; i++) cin >> v[i];
    for(int i = 2; i <= n; i++){
        int x;
        cin >> x;
        g[x].push_back(i);
    }
    dfs1(1);
    dfs2(1);
    LL ans = 0;
    for(auto x : s[1]) ans += x;
    cout << ans << '\n';

}