#include <bits/stdc++.h>
template <class T>
using Vec = std::vector<T>;
template <class F>
struct RecLambda: private F {
explicit RecLambda(F &&f): F(std::forward<F>(f)) { }
template <class... Args>
decltype(auto) operator () (Args&&... args) const {
return F::operator()(*this, std::forward<Args>(args)...);
}
};
constexpr int INF = 2000000000;
int main() {
int N;
std::cin >> N;
Vec<Vec<std::pair<int, int>>> graph(N);
for (int i = 1; i < N; ++i) {
int a, b, c;
std::cin >> a >> b >> c;
a -= 1;
b -= 1;
graph[a].emplace_back(b, c);
graph[b].emplace_back(a, c);
}
Vec<Vec<int>> a(N), b(N);
for (int i = 0; i < N; ++i) {
a[i].resize(graph[i].size());
b[i].resize(graph[i].size());
}
RecLambda([&](const auto dfs, const int u, const int p) -> std::pair<int, int> {
int sum = 0, dif = INF;
for (int i = 0; i < (int) graph[u].size(); ++i) {
const auto [v, c] = graph[u][i];
if (v == p) {
continue;
}
const auto [t1, t2] = dfs(v, u);
a[u][i] = t1 + c;
b[u][i] = std::max(t1, t2 + c);
sum += b[u][i];
dif = std::min(dif, b[u][i] - a[u][i]);
}
return std::make_pair(sum, sum - dif);
})(0, -1);
int ans = 0;
RecLambda([&](const auto dfs, const int u, const int p, const int up_t1, const int up_t2) -> void {
const auto size = (int) graph[u].size();
int sum = 0;
for (int i = 0; i < size; ++i) {
const auto [v, c] = graph[u][i];
if (v == p) {
a[u][i] = up_t1 + c;
b[u][i] = std::max(up_t1, up_t2 + c);
}
sum += b[u][i];
}
ans = std::max(ans, sum);
Vec<int> pref(size + 1, INF);
Vec<int> suff(size + 1, INF);
for (int i = 0; i < size; ++i) {
pref[i + 1] = std::min(pref[i], b[u][i] - a[u][i]);
suff[i + 1] = std::min(suff[i], b[u][size - i - 1] - a[u][size - i - 1]);
}
for (int i = 0; i < size; ++i) {
const auto [v, c] = graph[u][i];
if (v == p) {
continue;
}
const auto t1 = sum - b[u][i];
const auto t2 = t1 - std::min(pref[i], suff[size - i - 1]);
dfs(v, u, t1, t2);
}
})(0, -1, 0, 0);
std::cout << ans << '\n';
return 0;
}
