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#include <bits/stdc++.h>
#define dbg(x) " [" << #x << ": " << (x) << "] "
using namespace std;
template<typename A,typename B>
ostream& operator<<(ostream& out,const pair<A,B>& p) {
    return out << "(" << p.first << ", " << p.second << ")";
}
template<typename T>
ostream& operator<<(ostream& out,const vector<T>& c) {
    out << "{";
    for(auto it = c.begin(); it != c.end(); it++) {
        if(it != c.begin()) out << ", ";
        out << *it;
    }
    return out << "}";
}
const int N = 200001;
vector<vector<pair<int,int>>> g;
vector<vector<vector<long long>>> dp[N];
vector<int> u;
void dfs(int v) {
    u[v] = 1;
    vector<pair<int,int>> ch;
    for(auto [to,c] : g[v]) {
        if(!u[to]) {
            dfs(to);
            ch.push_back({to,c});
        }
    }
    int m = ch.size();
    vector<vector<long long>> ndp[m + 1];
    for(int i = 0; i <= m; i++) {
        ndp[i].resize(m - i + 1);
        for(int j = 0; i + j <= m; j++) {
            ndp[i][j].resize(m - i - j + 1);
        }
    }
    for(int r = 0; r < ch.size(); r++) {
        int to = ch[r].first;
        int c = ch[r].second;
        for(int i = 0; i <= r + 1; i++) {
            for(int j = 0; i + j <= r + 1; j++) {
                for(int k = 0; i + j + k <= r + 1; k++) {
                    ndp[i][j][k] = dp[v][i][j][k] + dp[to][0][0][0];
                    if(i + j + k + 1 <= r) {
                        ndp[i][j][k] = max(ndp[i][j][k],c + dp[to][0][1][0] + dp[v][i + 1][j][k]);
                        ndp[i][j][k] = max(ndp[i][j][k],c + dp[to][1][0][0] + dp[v][i][j + 1][k]);
                        ndp[i][j][k] = max(ndp[i][j][k],c + dp[to][0][0][0] + dp[v][i][j][k + 1]);
                    }
                    if(i) ndp[i][j][k] = max(ndp[i][j][k],c + dp[to][0][0][0] + dp[v][i - 1][j][k]);
                    if(j) ndp[i][j][k] = max(ndp[i][j][k],c + dp[to][1][0][0] + dp[v][i][j - 1][k]);
                    if(k) ndp[i][j][k] = max(ndp[i][j][k],c + dp[to][0][1][0] + dp[v][i][j][k - 1]);
                    ndp[i][j][k] = max(ndp[i][j][k],c + dp[to][0][0][1] + dp[v][i][j][k]);
                }
            }
        }
        for(int i = 0; i <= r + 1; i++) {
            for(int j = 0; i + j <= r + 1; j++) {
                for(int k = 0; i + j + k <= r + 1; k++) {
                    dp[v][i][j][k] = ndp[i][j][k];
                }
            }
        }
    }
}
void solve() {
    int n;
    cin >> n;
    g.resize(n);
    u.resize(n);
    for(int i = 0; i < n - 1; i++) {
        int a,b,c;
        cin >> a >> b >> c;
        a--;
        b--;
        g[a].push_back({b,c});
        g[b].push_back({a,c});
    }
    for(int v = 0; v < n; v++) {
        int x = g[v].size();
        dp[v].resize(x + 1);
        for(int i = 0; i <= x; i++) {
            dp[v][i].resize(x - i + 1);
            for(int j = 0; i + j <= x; j++) {
                dp[v][i][j].resize(x - i - j + 1);
                for(int k = 0; i + j + k <= x; k++) {
                    if(i || j || k) {
                        dp[v][i][j][k] = -1e18;
                    }
                }
            }
        }
    }
    dfs(0);
    cout << dp[0][0][0][0] << endl;
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int testNum = 1;
    //cin >> testNum;
    for(int i = 1; i <= testNum; i++) {
        solve();
    }
    return 0;
}