#include <bits/stdc++.h>
using namespace std;
#define FOR(i, j, k) for(int i=(j); i<=(k); i++)
#define FFOR(i, j, k) for(int i=(j); i<(k); i++)
#define DFOR(i, j, k) for(int i=(j); i>=(k); i--)
#define bug(x) cerr<<#x<<" = "<<(x)<<'\n'
#define pb push_back
#define mp make_pair
#define setbit(s, i) (s|=(1LL<<(i)))
#define bit(s, i) (((s)>>(i))&1LL)
#define mask(i) ((1LL<<(i)))
#define builtin_popcount __builtin_popcountll
typedef long long ll;
typedef long double ld;
template <typename T> inline void read(T &x){
char c;
bool nega=0;
while((!isdigit(c=getchar()))&&(c!='-'));
if(c=='-'){
nega=1;
c=getchar();
}
x=c-48;
while(isdigit(c=getchar())) x=x*10+c-48;
if(nega) x=-x;
}
template <typename T> inline void writep(T x){
if(x>9) writep(x/10);
putchar(x%10+48);
}
template <typename T> inline void write(T x){
if(x<0){
putchar('-');
x=-x;
}
writep(x);
}
template <typename T> inline void writeln(T x){
write(x);
putchar('\n');
}
#define taskname "beads"
int n;
vector <pair <int, int> > g[200001];
vector <pair <int, int> > h[200001];
bool done[200001];
ll f[200001][2];
ll all[200001];
ll dtp[200001];
multiset <ll> d[200001];
void make(int u){
if(done[u]) return;
done[u]=1;
f[u][0]=f[u][1]=0;
all[u]=0;
for(pair <int, int> v: h[u]){
dtp[v.first]=v.second;
make(v.first);
d[u].insert(f[v.first][0]+dtp[v.first]-max(f[v.first][0], f[v.first][1]+dtp[v.first]));
all[u]+=max(f[v.first][0], f[v.first][1]+v.second);
}
f[u][0]=all[u];
if(d[u].empty()) f[u][1]=-mask(40);
else f[u][1]=all[u]+*d[u].rbegin();
}
bool vs[200001];
vector <int> euler;
void dfs(int u){
vs[u]=1;
h[u].clear();
euler.pb(u);
for(pair <int, int> v: g[u]) if(!vs[v.first]){
h[u].pb(v);
dfs(v.first);
euler.pb(u);
}
}
vector <int> v;
int main(){
#ifdef Kanikou
if(fopen(taskname".inp", "r"))
freopen(taskname".inp", "r", stdin);
#endif // Kanikou
read(n);
{
int a, b, c;
FFOR(i, 1, n){
read(a);
read(b);
read(c);
g[a].pb(mp(b, c));
g[b].pb(mp(a, c));
}
}
ll ans=0;
int root=1;
dfs(1);
make(1);
ans=max(ans, f[1][0]);
for(int u: euler){
if(u==root) continue;
///make u become root
///push root down
d[root].erase(d[root].find(f[u][0]+dtp[u]-max(f[u][0], f[u][1]+dtp[u])));
all[root]-=max(f[u][0], f[u][1]+dtp[u]);
f[root][0]=all[root];
if(d[root].empty()) f[root][1]=-mask(40);
else f[root][1]=all[root]+*d[root].rbegin();
dtp[root]=dtp[u];
///bring u up
d[u].insert(f[root][0]+dtp[root]-max(f[root][0], f[root][1]+dtp[root]));
all[u]+=max(f[root][0], f[root][1]+dtp[root]);
f[u][0]=all[u];
if(d[u].empty()) f[u][1]=-mask(40);
else f[u][1]=all[u]+*d[u].rbegin();
dtp[u]=0;
root=u;
ans=max(ans, f[u][0]);
}
write(ans);
}
