#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int N, A[209], B[209], C[209], par[209], d[209][209]; vector<pair<int, int>>Z[209], X[209]; bool used[209];
int dp[209][4][2], maxn; vector<int>S;
void dfs(int pos, int pars) {
used[pos] = true; par[pos] = pars;
for (int i = 0; i < Z[pos].size(); i++) {
if (used[Z[pos][i].first] == true) continue;
X[pos].push_back(Z[pos][i]);
dfs(Z[pos][i].first, pos);
}
S.push_back(pos);
}
int main() {
cin >> N;
for (int i = 1; i <= N - 1; i++) {
cin >> A[i] >> B[i] >> C[i]; d[A[i]][B[i]] = C[i]; d[B[i]][A[i]] = C[i];
Z[A[i]].push_back(make_pair(B[i], C[i]));
Z[B[i]].push_back(make_pair(A[i], C[i]));
}
dfs(1, -1);
for (int i = 0; i <= N; i++) { for (int j = 0; j <= 4; j++) { dp[i][j][0] = -(1 << 30); dp[i][j][1] = -(1 << 30); } }
for (int i = 0; i < S.size(); i++) {
int pos = S[i];
// 次数 = 0 - 次数 = 1, 上を使う
int s = 0;
for (int j = 0; j < X[pos].size(); j++) {
int maxn = -1;
for (int k = 0; k <= 2; k++) maxn = max(maxn, dp[X[pos][j].first][k][0]);
if (maxn == -1 || s == -(1 << 30)) s = -(1 << 30);
else s += maxn;
}
dp[pos][0][1] = s;
dp[pos][1][0] = s;
// 次数 = 1, 上を使わない - 次数 = 2, 上を使う
for (int a1 = 0; a1 < X[pos].size(); a1++) {
int sum = 0;
for (int j = 0; j < X[pos].size(); j++) {
int maxn = -1, bit = 0; if (a1 == j) bit = 1;
for (int k = 0; k <= 2; k++) maxn = max(maxn, dp[X[pos][j].first][k][bit]);
if (maxn == -1 || sum == -(1 << 30)) sum = -(1 << 30);
else sum += maxn;
}
dp[pos][1][1] = max(dp[pos][1][1], sum);
if (pos != 1) dp[pos][2][0] = max(dp[pos][2][0], sum + d[par[pos]][pos] + d[X[pos][a1].first][pos]);
}
// 次数 = 2, 上を使わない
for (int a1 = 0; a1 < X[pos].size(); a1++) {
for (int a2 = 0; a2 < X[pos].size(); a2++) {
if (a1 == a2) continue;
int sum = 0;
for (int j = 0; j < X[pos].size(); j++) {
int maxn = -1, bit = 0; if (a1 == j || a2 == j) bit = 1;
for (int k = 0; k <= 2; k++) maxn = max(maxn, dp[X[pos][j].first][k][bit]);
if (maxn == -1 || sum == -(1 << 30)) sum = -(1 << 30);
else sum += maxn;
}
dp[pos][2][1] = max(dp[pos][2][1], sum + d[X[pos][a1].first][pos] + d[X[pos][a2].first][pos]);
}
}
}
int ret = -(1 << 30);
for (int i = 0; i <= 2; i++) ret = max(ret, dp[1][i][1]);
cout << ret << endl;
return 0;
}
