#include <bits/stdc++.h>
#define maxn 100086

using namespace std;

int n;
vector<pair<int, int> > v[maxn];
int ans, f[maxn], g[maxn], h[maxn];

void dfs(int i, int fa){
	int mx = 0, id = 0, sx = 0;
	for(auto it : v[i]){
		int to = it.first, co = it.second;
		if(to == fa) continue;
		dfs(to, i);
		if(g[to] >= mx) sx = mx, mx = g[to], id = to;
		else sx = max(sx, g[to]); 
	}
	f[i] = mx;
	int fmx = 0, hmx = 0;
	for(auto it : v[i]){
		int to = it.first, co = it.second;
		if(to == fa) continue;
		ans = max(ans, g[i] + g[to]);
		g[i] = max(g[i], g[to]);
		int fval = f[to] + co;
		int hval = h[to] + co;
		ans = max(ans, fval + hmx);
		ans = max(ans, fmx + hval);
		g[i] = max(g[i], hmx + hval);
		fmx = max(fmx, fval);
		hmx = max(hmx, hval);
	}
	for(auto it : v[i]){
		int to = it.first, co = it.second;
		if(to == fa) continue;
		int fval = f[to] + co + (id == to ? sx : mx);
		int hval = h[to] + co;
		f[i] = max(f[i], fval);
		h[i] = max(h[i], hval);
	}
//	printf("%d %d %d %d--\n", i, f[i], g[i], h[i]);
}

int main(){
	scanf("%d", &n);
	for(int i = 1;i < n;i++){
		int x, y, z;
		scanf("%d%d%d", &x, &y, &z);
		v[x].push_back({y, z});
		v[y].push_back({x, z});
	}
	dfs(1, 0);
//	printf("%d--\n", ans);
	ans = -ans;
	for(int i = 1;i <= n;i++) for(auto it : v[i]) ans += it.second;
	printf("%d", ans);
}