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#include <bits/stdc++.h>
using namespace std;
#define REP(i,a,b) for (int i = (a); i <= (b); ++i)
#define REPD(i,a,b) for (int i = (a); i >= (b); --i)
#define FORI(i,n) REP(i,1,n)
#define FOR(i,n) REP(i,0,int(n)-1)
#define mp make_pair
#define pb push_back
#define pii pair<int,int>
#define vi vector<int>
#define ll long long
#define SZ(x) int((x).size())
#define DBG(v) cerr << #v << " = " << (v) << endl;
#define FOREACH(i,t) for (typeof(t.begin()) i=t.begin(); i!=t.end(); i++)
#define fi first
#define se second

const int N = 200200;
const ll inf = 1LL * 1000100100 * 1000100100;

int n,m;
vector<pii> g[N];
int vert[N], par[N];

ll dp[N][4];
ll D[2][4][2][2][N*2];

void dfs(int u, int parent = -1) {
	FOR(i,SZ(g[u])) {
		int v = g[u][i].fi;
		if (v == parent) {
			par[u] = v;
		} else {
			dfs(v, u);
		}
	}
	vert[m++] = u;
}
int vvs[N];
int main() {
	scanf("%d", &n);
	FOR(i,n-1) {
		int a,b,c;
		scanf("%d%d%d", &a, &b, &c);
		//a=1; b=i+2; c=rand()%1000000-500000;
		a--; b--;
		g[a].emplace_back(b,c);
		g[b].emplace_back(a,c);
	}
	FOR(i,n) random_shuffle(g[i].begin(), g[i].end());
	dfs(0);
	FOR(i,n) vvs[i]=SZ(g[i]);
	sort(vvs,vvs+n);
	//cerr << vvs[n-1] << " " << vvs[n-2] << " " << vvs[n-3] << "\n";
	int MAXMAXTWOS = 10000, posmx = n-1;
	ll MAXOP = 4e7;
	while (posmx>=0 && vvs[posmx]>=1e4) posmx--;
	ll totalop_min = 0, totalop_max = 1;
	FOR(i,n) {
		if (i <= posmx) totalop_min += 1LL*vvs[i]*vvs[i];
		else totalop_max += vvs[i];
	}
	while (totalop_min + totalop_max*vvs[posmx] > MAXOP) {
		//cerr << totalop_min << " + " << totalop_max << " * " << vvs[posmx] << " is too much\n";
		totalop_min -= 1LL*vvs[posmx]*vvs[posmx];
		totalop_max += vvs[posmx];
		posmx--;
	}
	MAXMAXTWOS = (MAXOP-totalop_min) / totalop_max;
	//cerr << totalop_min << " + " << totalop_max << " * " << vvs[posmx] << " is ok\n";
	//cerr << totalop_min << " + " << totalop_max << " * " << MAXMAXTWOS << " is ok\n";
	ll totalop = 0;
	FOR(ii,n) {
		int u = vert[ii];
		int VTWOS = min(SZ(g[u]) / 2, MAXMAXTWOS), MAXTWOS = VTWOS * 2 + 1;
		totalop += 1LL * MAXTWOS * SZ(g[u]);
		//int VTWOS = SZ(g[u]) / 2, MAXTWOS = VTWOS * 2 + 1;
		FOR(L,4) FOR(top,2) FOR(ones,2) FOR(twos,MAXTWOS) {
			D[0][L][top][ones][twos] = -inf;
			D[1][L][top][ones][twos] = -inf;
		}
		FOR(L,4) D[0][L][0][0][0+VTWOS] = 0;
		FOR(i,SZ(g[u])) {
			int v = g[u][i].fi, c = g[u][i].se;
			if (v == par[u]) continue;
			// D[layer=0/1][L=0..3][top=0/1][ones=0/1][twos=-N..N]
			FORI(L,3) FOR(ones,2) FOR(twos,MAXTWOS) {
				D[1][L][1][ones][twos] = max(D[1][L][1][ones][twos], D[0][L][0][ones][twos] + c + dp[v][L-1]);
			}
			FOR(L,4) FOR(top,2) FOR(ones,2) FOR(twos,MAXTWOS) {
				ll DC = D[0][L][top][ones][twos];
				                    D[1][L][top][ones][twos]   = max(D[1][L][top][ones][twos]  , DC + max(c + dp[v][3], dp[v][0]));
				if (twos+1<MAXTWOS) D[1][L][top][ones][twos+1] = max(D[1][L][top][ones][twos+1], DC + c + dp[v][2]               );
				if (twos > 0)       D[1][L][top][ones][twos-1] = max(D[1][L][top][ones][twos-1], DC + c + dp[v][0]               );
				                    D[1][L][top][!ones][twos]  = max(D[1][L][top][!ones][twos] , DC + c + dp[v][1]               );
			}
			FOR(L,4) FOR(top,2) FOR(ones,2) FOR(twos,MAXTWOS) {
				D[0][L][top][ones][twos] = D[1][L][top][ones][twos];
				D[1][L][top][ones][twos] = -inf;
			}
		}
		dp[u][0] = D[0][0][0][0][VTWOS];
		FORI(L,3) dp[u][L] = D[0][L][1][0][VTWOS];
	}
	printf("%lld\n", dp[0][0]);
	//cout << totalop << "\n";
	return 0;
}