// fest
#include <bits/stdc++.h>
#define pb push_back
#define F first
#define S second
#define y1 dasdasfasfas
#define x1 wqdadfasfasfas
#define All(c) c.begin(), c.end()
#define SZ(A) (int((A).size()))
#define umap unordered_map
#define FILENAME ""
#define __ fflush(stdout)
typedef long long ll;
typedef long double ld;
using namespace std;
void FREOPEN() {
#ifdef COMP
freopen(".in", "r", stdin);
freopen("1.out", "w", stdout);
#endif
}
inline double Time() {return (clock() * 1.0) / CLOCKS_PER_SEC; }
const int N = 200500, inf = 1e9 * 2, MOD = (int)1e9 + 7;
char CH[N];
const ll INF = 1e18;
const int dx[] = {1, -1, 0, 0, -1, 1, -1, 1};
const int dy[] = {0, 0, 1, -1, -1, 1, 1, -1};
int dp[N][2];
vector<pair<int, int> > g[N];
void dfs(int v, int pr, int last) {
dp[v][0] = 0;
dp[v][1] = -inf;
for (auto i : g[v]) {
int u = i.F;
int c = i.S;
if (u == pr) continue;
dfs(u, v, c);
dp[v][0] += max(dp[u][0], dp[u][1]);
}
for (auto i : g[v]) {
int u = i.F;
int c = i.S;
if (u == pr) continue;
dp[v][1] = max(dp[v][1], last + (dp[v][0] - max(dp[u][0], dp[u][1])) + c + dp[u][0]);
}
}
int main() {
FREOPEN();
int n;
cin >> n;
for (int i = 2; i <= n; i++) {
int x, y, c;
scanf("%d %d %d", &x, &y, &c);
g[x].pb({y, c});
g[y].pb({x, c});
}
int ans = 0;
for (int root = 1; root <= n; root++) {
dfs(root, 0, 0);
ans = max(ans, dp[root][0]);
}
cout << ans;
return 0;
}
