/* Author : Mychecksdead */
#include<bits/stdc++.h>
using namespace std;
#define ll long long int
#define MOD (1000000000+7)
#define MOD1 (998244353)
#define pb push_back
#define all(x) x.begin(), x.end()
#define en cout << '\n'
#define ff first
#define ss second
#define pii pair<int,int>
#define vi vector<int>
const int N = 5000+100, M = 1e5+10, K = 52, MX = 30;
int n;
vi g[N];
array<ll, 2> a[N];
ll dp[N][N];
void dfs(int v){
for(int i = 1; i <= n; ++i) dp[v][i] = (i == a[v][0] ? 0 : a[v][1]);
for(int u: g[v]){
dfs(u);
for(int i = 1; i <= n; ++i) dp[v][i] += dp[u][i];
}
for(int i = n-1; i >= 1; --i) dp[v][i] = min(dp[v][i], dp[v][i + 1]);
}
void solve(){
cin >> n;
vi val;
for(int i = 1; i <= n; ++i){
int x; cin >> x;
if(x < i)
g[x].pb(i);
cin >> a[i][0] >> a[i][1];
val.pb(a[i][0]);
}
sort(all(val));
val.erase(unique(all(val)), val.end());
for(int i = 1; i <= n; ++i){
a[i][0] = lower_bound(all(val), a[i][0]) - val.begin() + 1;
}
dfs(1);
cout << dp[1][1];
}
int main(){
cin.tie(0); ios::sync_with_stdio(0);
int tt = 1, aa;
// freopen("in.txt", "r", stdin);
// freopen("out.txt", "w", stdout);
while(tt--){
solve();
en;
}
cerr<<"time taken : "<<(float)clock()/CLOCKS_PER_SEC<<" seconds\n";
return 0;
}
