#include <bits/stdc++.h>
using namespace std;
#define all(x) (x).begin(), (x).end()
#define sz(x) ((int) x.size())
#define show(x) cerr << #x << " is " << x << endl;
#define show2(x, y) cerr << #x << " is " << x << ", " << #y << " is " << y << endl;
typedef long long lint;
typedef pair<lint, lint> ii;
vector<int> adj[200005];
map<int, lint> dp[200005];
lint cost[200005];
lint original[200005];
void dfs(int u){
for(int v : adj[u]){
dfs(v);
if(sz(dp[u]) < sz(dp[v])) swap(dp[u], dp[v]);
map<int, lint> &cur = dp[u];
for(ii x : dp[v]){
if(cur.count(x.first)) cur[x.first] += x.second;
else cur[x.first] = x.second;
}
}
lint O = original[u]; lint C = cost[u];
map<int, lint> &cur = dp[u];
if(cur.count(O)) cur[O] += C ;
else cur[O] = C;
while(true){
auto it = cur.upper_bound(O);
if(it == cur.end()) break;
if(it->second > C){
it->second -= C;
break;
}
else{
C -= it->second;
cur.erase(it);
}
}
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0);
lint ans = 0;
int n; cin >> n;
for(int i = 1;i <= n;i++){
int a; cin >> a >> original[i] >> cost[i];
original[i] *= -1;
if(i != a) adj[a].push_back(i);
ans += cost[i];
}
dfs(1);
for(ii x : dp[1]) ans -= x.second;
cout << ans;
}
