#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int , int> pii;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int maxn = 1e4 + 10;
const ll mod = 1e9+7;
#define pb push_back
#define endl '\n'
#define dokme(x) cout << x , exit(0)
#define ms(x , y) memset(x , y , sizeof x)
ll pw(ll a, ll b, ll md = mod){ll res = 1;while(b){if(b&1){res=(a*res)%md;}a=(a*a)%md;b>>=1;}return(res);}
int n;
int dp[maxn][2];
vector < pii > adj[maxn];
void dfs(int v , int par = 0){
for(auto [u , w] : adj[v])if(u ^ par)
dfs(u , v),
dp[v][0] += max(dp[u][0] , dp[u][1] + w);
dp[v][1] = -2e9 - 10;
for(auto [u , w] : adj[v])if(u ^ par)
dp[v][1] = max(dp[v][1] , dp[v][0] + w + dp[u][0] - max(dp[u][0] , dp[u][1] + w));
}
int32_t main(){
ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
cin >> n;
for(int i = 1 ; i < n ; i ++){
int a , b , c;
cin >> a >> b >> c;
adj[a].pb({b , c});
adj[b].pb({a , c});
}
int ans = 0;
for(int i = 1 ; i <= n ; i ++){
ms(dp , 0) , dfs(i) , ans = max(ans , dp[i][0]);
}
cout << ans;
return(0);
}
