//雪花飄飄北風嘯嘯
//天地一片蒼茫
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;
#define ll long long
#define ii pair<ll,ll>
#define iii pair<ii,ll>
#define fi first
#define se second
#define endl '\n'
#define debug(x) cout << #x << " is " << x << endl
#define rep(x,start,end) for(auto x=(start)-((start)>(end));x!=(end)-((start)>(end));((start)<(end)?x++:x--))
#define all(x) (x).begin(),(x).end()
#define sz(x) (int)(x).size()
#define indexed_set tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>
//change less to less_equal for non distinct pbds, but erase will bug
mt19937 rng(chrono::system_clock::now().time_since_epoch().count());
int n;
vector<ii> al[200005];
map<ii,int> memo[2];
int dp(int i,int p,int flag){
if (memo[flag].count(ii(i,p))) return memo[flag][ii(i,p)];
ll total=0;
vector<int> v={(int)-1e9};
for (auto &it:al[i]){
if (it.fi==p) continue;
ll temp0=dp(it.fi,i,0);
ll temp1=dp(it.fi,i,1);
ll val=max(temp0,temp1+it.se);
total+=val;
v.push_back(temp0+it.se-val);
}
if (flag){
sort(all(v));
total+=v.back();
}
return memo[flag][ii(i,p)]=total;
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin.exceptions(ios::badbit | ios::failbit);
cin>>n;
int a,b,c;
rep(x,1,n){
cin>>a>>b>>c;
al[a].push_back(ii(b,c));
al[b].push_back(ii(a,c));
}
int ans=0;
rep(x,1,n+1) ans=max(ans,dp(x,-1,0));
cout<<ans<<endl;
}
