#include <bits/stdc++.h>
using namespace std;
#define TRACE(x) cerr << #x << " :: " << x << endl
#define _ << " " <<
#define SZ(x) (int)(x).size()
#define ALL(x) (x).begin(),(x).end()
#define FOR(i,a,b) for(int i=(a);i<=(b);++i)
#define RFOR(i,a,b) for(int i=(a);i>=(b);--i)
typedef long long ll;
//const int mxN = 2e5+5;
const int mxN = 5e3+5;
const ll inf = 1e18;
int N, A[mxN], H[mxN], C[mxN], V;
vector<int> al[mxN], vals;
ll dp[mxN][mxN];
void dfs(int u) {
FOR(x,0,V-1) dp[u][x] = 0;
for (int v : al[u]) {
dfs(v);
FOR(x,0,V-1){
ll cur = dp[v][x] + C[v];
if (x <= H[v]) cur = min(cur, dp[v][H[v]]);
dp[u][x] += cur;
}
}
//cout << u << ": ";
//FOR(x,0,V-1){
// cout << dp[u][x] << ' ';
//}
//cout << endl;
}
int main() {
ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin >> N;
FOR(i,1,N){
cin >> A[i] >> H[i] >> C[i];
if (i != 1) al[A[i]].push_back(i);
vals.push_back(H[i]);
}
vals.push_back(1);
sort(ALL(vals));
vals.resize(unique(ALL(vals))-vals.begin());
FOR(i,1,N){
H[i] = lower_bound(ALL(vals),H[i])-vals.begin();
}
V = SZ(vals);
dfs(1);
cout << min(dp[1][0] + C[1], dp[1][H[1]]) << '\n';
}
