#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)
#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 10001;
int n;
vpi adj[MX];
pi comb(pi ret, pi x, int len) {
ret.s = max(ret.s+max(x.f,x.s),ret.f+len+x.f);
ret.f += max(x.f,x.s);
return ret;
}
pi dfs(int cur, int pre) {
pi ret = {0,-MOD}; // no needed, needed
for (auto a: adj[cur]) if (a.f != pre) {
pi x = dfs(a.f,cur); x.s += a.s;
ret = comb(ret,x,a.s);
}
// cout << cur << " " << ret.f << " " << ret.s << "\n";
return ret;
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0);
cin >> n;
F0R(i,n-1) {
int a,b,c; cin >> a >> b >> c;
adj[a].pb({b,c}), adj[b].pb({a,c});
}
int ans = 0;
// dfs(5,0);
FOR(i,1,n+1) {
// cout << dfs(i,0).f << "\n";
ans = max(ans,dfs(i,0).f);
}
cout << ans;
}
/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( )
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/
