#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb push_back
const int N = 2e5 + 5;
ll dp[N][2][2];
vector<array<int, 2>> g[N];
void dfs(int s, int e = -1) {
dp[s][0][0] = 0, dp[s][1][0] = dp[s][1][1] = dp[s][0][1] = -1e12;
for (auto [u, w] : g[s]) {
if (u == e) continue;
dfs(u, s);
dp[s][0][0] += max({dp[u][0][0], dp[u][0][1], dp[u][1][0] + w});
}
for (auto [u, w1] : g[s]) {
if (u == e) continue;
ll bs = dp[u][0][0] + w1;
for (auto [v, w2] : g[s]) {
if (v == e || v == u) continue;
bs += max({dp[v][0][0], dp[v][0][1], dp[v][1][0] + w2});
}
dp[s][1][0] = max(dp[s][1][0], bs);
}
// cout << s << ' ' << dp[s][1][0] << '\n';
for (auto [u, w1] : g[s]) {
if (u == e) continue;
for (auto [v, w2] : g[s]) {
if (v == e || v == u) continue;
ll bs = max(dp[u][0][0], dp[u][0][1]) + max(dp[v][0][0], dp[v][0][1]) + w1 + w2;
for (auto [t, w3] : g[s]) {
if (t == v || t == u || t == e) continue;
bs += max({dp[t][0][0], dp[t][0][1], dp[t][1][0] + w3});
}
dp[s][0][1] = max(dp[s][0][1], bs);
}
ll bs = dp[u][1][1] + w1;
for (auto [v, w2] : g[s]) {
if (v == e || v == u) continue;
bs += max({dp[v][0][0], dp[v][0][1], dp[v][1][0] + w2});
}
dp[s][0][1] = max(dp[s][0][1], bs);
}
for (auto [u, w1] : g[s]) {
if (u == e) continue;
ll bs = dp[u][0][1] + w1;
for (auto [v, w2] : g[s]) {
if (v == e || u == v) continue;
bs += max({dp[v][0][0], dp[v][0][1], dp[v][1][0] + w2});
}
dp[u][1][1] = max(dp[u][1][1], bs);
}
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
int n;
cin >> n;
for (int i = 1; i < n; ++i) {
int u, v, w;
cin >> u >> v >> w;
g[u].pb({v, w});
g[v].pb({u, w});
}
dfs(1);
cout << max(dp[1][0][0], dp[1][0][1]) << '\n';
}
