#include <iostream>
#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll maxn = 2*1e5+5, INF = 4e18+9;
vector<int> find_cycle(vector<vector<int>> &adj){
int n = adj.size()-1;
vector<int> cyc(n+1, 0);
vector<int> vis(n+1, 0), pa(n+1, -1);
auto dfs = [&](auto dfs, int u) -> void{
vis[u] = 1;
for(int v : adj[u]){
if(vis[v] == 1){
//cycle found
int t = u;
while(t != v){
cyc[t] = v;
t = pa[t];
}
cyc[v] = v;
}
if(!vis[v]){
pa[v] = u;
dfs(dfs, v);
}
}
vis[u] = 2;
};
for(int i = 1; i <= n; i++){
if(vis[i]) continue;
dfs(dfs, i);
}
return cyc;
}
void solve(){
int n;
cin >> n;
vector<vector<int>> adj(n+1), adj_rev(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_rev[v].push_back(i);
}
vector<int> cyc = find_cycle(adj);
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 || cyc[node]) 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), res(n+1);
auto dfs = [&](auto dfs, int u, int p) -> void{
for(int v : adj_rev[u]){
if(v == p || cyc[v]) continue;
dfs(dfs, v, u);
add(dp[u], dp[v]);
}
fix(u, dp[u], h[u], c[u]);
};
for(int i = 1; i <= n; i++){
if(cyc[i]){
dfs(dfs, i, i);
add(res[cyc[i]], dp[i]);
}
}
ll ans = 0;
for(int i = 1; i <= n; i++){
ll pf = 0, mn = INF;
if(res[i].size() == 0) mn = 0;
for(auto it : res[i]){
pf += it.second;
mn = min(mn, pf);
}
ans += mn;
}
cout << ans;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
solve();
}
