#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
#define pb push_back
#define all(a) a.begin(), a.end()
#define sz(a) ((int)a.size())
#ifdef ABS
void db() {}
template <typename T>
ostream& operator << (ostream &o, vector <T> vec) {
    o << "{"; int f = 0;
    for (T i : vec) o << (f++ ? " " : "") << i;
    return o << "}";
}
template <typename T, typename ...U> void db(T i, U ...j) { cerr << i << " ", db(j...); }
#define ppr(c, x...) cerr << "\e[1;" << c << "m" , db(__LINE__, "[" + string(#x) + "]", x), cerr << "\e[0m" << endl
#define bug(x...) ppr(32, x)
#define bugv(x...) ppr(36, vector(x))
#define safe ppr(33, "safe")
#else
#define bug(x...) void(0)
#define bugv(x...) void(0)
#define safe void(0)
#endif
const int mod = 998244353, N = 100007;

vector<pii> g[N];
int dp[N];

void dfs(int i, int p) {
    dp[i] = 0;
    for (auto [j, w] : g[i]) if (j != p) {
        dfs(j, i);
        dp[i] = max(dp[i], dp[j] + w);
    }
}

int ans;

void dfs2(int i, int p, int mx, int mx2) {
    array<int, 4> best({mx, 0, 0, 0});
    for (auto [j, w] : g[i]) if (j != p) {
        for (int _i = 0; _i < 4; ++_i) if (best[_i] < w + dp[j]) {
            for (int _j = 3; _j > _i; --_j)
                best[_j] = best[_j - 1];
            best[_i] = w + dp[j];
            break;
        }
    }
    ans = max(ans, best[0] + best[1] + best[2] + best[3]);
    ans = max(ans, (mx >= best[1] ? best[0] + best[1] + best[2] - mx : best[0] + best[1]) + mx2);
    for (auto [j, w] : g[i]) if (j != p) {
        int tmp = w + dp[j] == best[0] ? best[1] : best[0];
        int tmp2 = max(mx2, w + dp[j] >= best[1] ? best[0] + best[1] + best[2] - w - dp[j] : best[0] + best[1]);
        dfs2(j, i, tmp + w, tmp2);
    }
}

int main() {
    ios::sync_with_stdio(false), cin.tie(0);
    int n;
    cin >> n;
    int tot = 0;
    for (int i = 0; i < n - 1; ++i) {
        int x, y, z;
        cin >> x >> y >> z;
        --x, --y;
        g[x].emplace_back(y, z), g[y].emplace_back(x, z);
        tot += z;
    }
    dfs(0, -1);
    //safe;
    dfs2(0, -1, 0, 0);
    cout << 2 * tot - ans << '\n';
}