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#include <bits/stdc++.h>
using namespace std;

const int N = 2e5 + 5;
const long long inf = 1e18 + 1;

int n;
vector<pair<int, int> > kraw[N];
long long dp[4][N];
bitset<N> odw;
long long tmp[2 * N][2][2][4];

void clear(int t) {
	for (int i = -t; i <= t; i++) {
		for (int j = 0; j < 2; j++) {
			for (int k = 0; k < 2; k++) {
				for (int l = 0; l < 4; l++) {
					tmp[N + i][j][k][l] = -inf;
				}
			}
		}
	}
}

void dfs(int x) {
	odw[x] = true;
	for (auto v : kraw[x]) {
		if (!odw[v.first]) {
			dfs(v.first);
		}
	}


	int ind = 0;
	clear(kraw[x].size() + 1);
	tmp[N][0][0][0] = 0;
	int licz = 0;
	for (auto v : kraw[x]) {
		if (!odw[v.first]) {
			ind ^= 1;
			licz++;
			int d = min(licz, (int)kraw[x].size() - licz + 5);
			for (int i = N - d; i <= N + d; i++) {
				long long ile = tmp[i][ind ^ 1][0][0] + dp[0][v.first];
ile = max(ile, tmp[i][ind ^ 1][0][0] + dp[3][v.first] + v.second);
ile = max(ile, tmp[i - 1][ind ^ 1][0][0] + dp[0][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][0 ^ 1][0] + dp[1][v.first] + v.second);
ile = max(ile, tmp[i + 1][ind ^ 1][0][0] + dp[2][v.first] + v.second);
tmp[i][ind][0][0] = ile;


ile = tmp[i][ind ^ 1][0][1] + dp[0][v.first];
ile = max(ile, tmp[i][ind ^ 1][0][1] + dp[3][v.first] + v.second);
ile = max(ile, tmp[i - 1][ind ^ 1][0][1] + dp[0][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][0 ^ 1][1] + dp[1][v.first] + v.second);
ile = max(ile, tmp[i + 1][ind ^ 1][0][1] + dp[2][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][0][0] + v.second + dp[1 - 1][v.first]);
tmp[i][ind][0][1] = ile;


ile = tmp[i][ind ^ 1][0][2] + dp[0][v.first];
ile = max(ile, tmp[i][ind ^ 1][0][2] + dp[3][v.first] + v.second);
ile = max(ile, tmp[i - 1][ind ^ 1][0][2] + dp[0][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][0 ^ 1][2] + dp[1][v.first] + v.second);
ile = max(ile, tmp[i + 1][ind ^ 1][0][2] + dp[2][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][0][0] + v.second + dp[2 - 1][v.first]);
tmp[i][ind][0][2] = ile;

ile = tmp[i][ind ^ 1][0][3] + dp[0][v.first];
ile = max(ile, tmp[i][ind ^ 1][0][3] + dp[3][v.first] + v.second);
ile = max(ile, tmp[i - 1][ind ^ 1][0][3] + dp[0][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][0 ^ 1][3] + dp[1][v.first] + v.second);
ile = max(ile, tmp[i + 1][ind ^ 1][0][3] + dp[2][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][0][0] + v.second + dp[3 - 1][v.first]);
tmp[i][ind][0][3] = ile;

ile = tmp[i][ind ^ 1][1][0] + dp[0][v.first];
ile = max(ile, tmp[i][ind ^ 1][1][0] + dp[3][v.first] + v.second);
ile = max(ile, tmp[i - 1][ind ^ 1][1][0] + dp[0][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][1 ^ 1][0] + dp[1][v.first] + v.second);
ile = max(ile, tmp[i + 1][ind ^ 1][1][0] + dp[2][v.first] + v.second);
tmp[i][ind][1][0] = ile;

ile = tmp[i][ind ^ 1][1][1] + dp[0][v.first];
ile = max(ile, tmp[i][ind ^ 1][1][1] + dp[3][v.first] + v.second);
ile = max(ile, tmp[i - 1][ind ^ 1][1][1] + dp[0][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][1 ^ 1][1] + dp[1][v.first] + v.second);
ile = max(ile, tmp[i + 1][ind ^ 1][1][1] + dp[2][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][1][0] + v.second + dp[1 - 1][v.first]);
tmp[i][ind][1][1] = ile;

ile = tmp[i][ind ^ 1][1][2] + dp[0][v.first];
ile = max(ile, tmp[i][ind ^ 1][1][2] + dp[3][v.first] + v.second);
ile = max(ile, tmp[i - 1][ind ^ 1][1][2] + dp[0][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][1 ^ 1][2] + dp[1][v.first] + v.second);
ile = max(ile, tmp[i + 1][ind ^ 1][1][2] + dp[2][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][1][0] + v.second + dp[2 - 1][v.first]);
tmp[i][ind][1][2] = ile;

ile = tmp[i][ind ^ 1][1][3] + dp[0][v.first];
ile = max(ile, tmp[i][ind ^ 1][1][3] + dp[3][v.first] + v.second);
ile = max(ile, tmp[i - 1][ind ^ 1][1][3] + dp[0][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][1 ^ 1][3] + dp[1][v.first] + v.second);
ile = max(ile, tmp[i + 1][ind ^ 1][1][3] + dp[2][v.first] + v.second);
ile = max(ile, tmp[i][ind ^ 1][1][0] + v.second + dp[3 - 1][v.first]);
tmp[i][ind][1][3] = ile;

			}
		}
	}
	for (int i = 0; i < 4; i++) {
		dp[i][x] = tmp[N][ind][0][i];
	}
	odw[x] = false;
}

int main() {
	scanf("%d", &n);
	for (int i = 1; i < n; i++) {
		int a, b, w;
		scanf("%d%d%d", &a, &b, &w);
		kraw[a].push_back(make_pair(b, w));
		kraw[b].push_back(make_pair(a, w));
	}

	// for (int i = 1; i <= n; i++) {
	// 	for (int j = 1; j <= 4; j++) {
	// 		dp[j][i] = -inf;
	// 	}
	// }
	int lisc = 0;
	for (int i = 1; i <= n; i++) {
		if ((int)kraw[i].size() > 1) {
			lisc++;
			// cout << "witam " << i << endl;
		}
	}
	// cout << "siema " << lisc << endl;
	if (lisc == 1) {
		printf("0\n");
		return 0;
	}
	dfs(1);

	printf("%lld\n", dp[0][1]);
	// for (int i = 1; i <= n; i++) {
	// 	printf("dp[%d] = (%lld, %lld, %lld, %lld)\n", i, dp[0][i], dp[1][i], dp[2][i], dp[3][i]);
	// }


}