#include<bits/stdc++.h>
#include<fstream>
using namespace std;
#define sz(a) (int)a.size()
#define ALL(v) v.begin(), v.end()
#define ALLR(v) v.rbegin(), v.rend()
#define ll long long
#define pb push_back
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
#define ld long double
#define vt vector
#include<fstream>
#define fi first
#define se second
#define pll pair<ll, ll>
#define pii pair<int, int>
#define mpp make_pair
const ld PI = 3.14159265359, prec = 1e-9;;
//using u128 = __uint128_t;
//const int x[4] = {1, 0, -1, 0};
//const int y[4] = {0, -1, 0, 1};
const ll mod = 1e9 + 7, pr = 31;
const int mxn = 2e5 + 5, mxq = 1e5 + 5, sq = 500, mxv = 5e4 + 1;
//const int base = (1 <<18);
const ll inf = 1e9 + 5, neg = -69420, inf2 = 1e14;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
// have fun!
int n;
vt<int>adj[mxn + 1];
ll a[mxn + 1], h[mxn + 1], c[mxn + 1];
map<ll, ll>mp[mxn + 1];
void dfs(int s, int pre){
for(auto i: adj[s]){
if(i != pre){
dfs(i, s);
if(sz(mp[i]) > sz(mp[s])){
swap(mp[s], mp[i]);
}
for(auto j: mp[i])mp[s][j.fi] += j.se;
}
}
mp[s][h[s]] += c[s];
ll lft = c[s];
while(1){
auto it = mp[s].lower_bound(h[s]);
if(it == mp[s].begin())break;
--it;
if((*it).se <= lft){
lft -= (*it).se; mp[s].erase(it);
}else{
(*it).se -= lft; break;
}
}
}
void solve(){
cin >> n;
ll tot = 0;
for(int i = 1; i <= n; i++){
cin >> a[i] >> h[i] >> c[i]; tot += c[i];
if(i != 1)adj[a[i]].pb(i);
}
dfs(1, -1);
ll ans = 0;
for(auto i: mp[1]){
ans += i.se;
}
cout << tot - ans;
}
signed main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
//freopen("DATA.inp", "r", stdin);
//freopen("DATA.out", "w", stdout);
int tt; tt = 1;
while(tt--){
solve();
}
return(0);
}
