#include <iostream>
#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll maxn = 2*1e5+5, INF = 4e18+9;
void solve(){
int n;
cin >> n;
vector<vector<int>> adj(n+1);
vector<ll> h(n+1), c(n+1);
int root = 1;
ll sumc = 0;
for(int i = 1; i <= n; i++){
int v;
cin >> v >> h[i] >> c[i];
sumc += c[i];
adj[i].push_back(v);
adj[v].push_back(i);
}
auto add = [&](map<ll, ll> &u, map<ll, ll> &v){
if(u.size() < v.size()) swap(u, v);
for(auto it : v){
ll h = it.first, c = it.second;
u[h] += c;
}
};
auto fix = [&](int node, map<ll, ll> &u, ll h, ll d){
u[h] -= d;
u[h+1] += d;
u[0] += d;
if(u[h] >= 0 || node == root) return;
d = -u[h];
u[h] = 0;
auto it = u.lower_bound(h);
while(it != u.begin()){
it = prev(it);
if(it->second <= d){
d -= it->second;
it = u.erase(it);
}else{
it->second -= d;
break;
}
}
};
vector<map<ll, ll>> dp(n+1);
auto dfs = [&](auto dfs, int u, int p) -> void{
for(int v : adj[u]){
if(v == p) continue;
dfs(dfs, v, u);
add(dp[u], dp[v]);
}
fix(u, dp[u], h[u], c[u]);
};
dfs(dfs, 1, 1);
ll ans = INF, res = 0;
for(auto it : dp[1]){
res += it.second;
ans = min(ans, res);
}
cout << ans;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
solve();
}
