#include <bits/stdc++.h>
using namespace std;
#define int long long
__int32_t main() {
ios::sync_with_stdio(0); cin.tie(0);
int n; cin >> n;
vector<int> par(n);
vector<vector<int>> children(n);
vector<int> value(n);
vector<int> cost(n);
set<int> values;
for (int i = 0; i < n; i++) {
cin >> par[i] >> value[i] >> cost[i];
par[i]--;
if (par[i] != i) children[par[i]].push_back(i);
values.insert(value[i]);
}
vector<int> dist_values;
for (int e : values) dist_values.push_back(e);
vector<vector<int>> dp(n, vector<int>(dist_values.size()));
vector<vector<int>> dpleq(n, vector<int>(dist_values.size()));
function<void(int)> dfs = [&](int v) {
for (int c : children[v]) {
dfs(c);
}
for (int val = 0; val < dist_values.size(); val++) {
dp[v][val] = dist_values[val] == value[v] ? 0 : cost[v];
for (int c : children[v]) dp[v][val] += dpleq[c][val];
}
dpleq[v] = dp[v];
for (int val = dist_values.size() - 2; val >= 0; val--) dpleq[v][val] = min(dpleq[v][val], dpleq[v][val+1]);
};
dfs(0);
cout << dpleq[0][0] << "\n";
return 0;
}
