#include<bits/stdc++.h>
#pragma GCC optimize("unroll-loops,no-stack-protector,Ofast")
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pll;
const ll MOD=1e9+7;
const ll MOD2=998244353;
const ll N=2e5+5;
const ld pi=acos(-1);
const ll INF=(1LL<<60);
#define SQ(i) ((i)*(i))
#define REP(i,n) for(ll i=0;i<n;i++)
#define REP1(i,n) for(ll i=1;i<=n;i++)
#define pb push_back
#define mp make_pair
#define X first
#define Y second
#define setp setprecision
#define lwb lower_bound
#define SZ(_a) (ll)_a.size()
vector<pll> v[N];
ll n,x,y,c,ans;
multiset<ll,greater<ll> > ms[N];
ll pac[N],dp[N],sum[N];
void DFS(ll nd,ll pa){
for(auto i:v[nd]){
if(i.X!=pa){
pac[i.X]=i.Y;
DFS(i.X,nd);
sum[nd]+=dp[i.X];
ms[nd].insert(sum[i.X]-dp[i.X]+i.Y);
}
}
dp[nd]=max(sum[nd],(SZ(ms[nd])>0?sum[nd]+*ms[nd].begin()+pac[nd]:0LL));
}
void move(ll rt,ll to,ll ed){
//remove
sum[rt]-=dp[to];
ms[rt].erase(ms[rt].find(sum[to]-dp[to]+ed));
pac[rt]=ed;
dp[rt]=max(sum[rt],(SZ(ms[rt])>0?sum[rt]+*ms[rt].begin()+pac[rt]:0LL));
sum[to]+=dp[rt];
pac[to]=0;
ms[to].insert(sum[rt]-dp[rt]+ed);
dp[to]=max(sum[to],(SZ(ms[to])>0?sum[to]+*ms[to].begin()+pac[to]:0LL));
}
void reroot(ll nd,ll pa){
ans=max(ans,sum[nd]);
for(auto i:v[nd]){
if(i.X==pa)continue;
move(nd,i.X,i.Y);
reroot(i.X,nd);
move(i.X,nd,i.Y);
}
}
int main(){
ios_base::sync_with_stdio(0);cin.tie(0);
cin>>n;
REP1(i,n-1){
cin>>x>>y>>c;
v[x].pb(mp(y,c));
v[y].pb(mp(x,c));
}
DFS(1,0);
reroot(1,0);
cout<<ans<<"\n";
return 0;
}
/*
10
4 10 2
1 2 21
1 3 13
6 7 1
7 9 5
2 4 3
2 5 8
1 6 55
6 8 34
*/
