#include<bits/stdc++.h>
#define int long long
using namespace std;
int n,a[1005][1005],ans;
bool point[1005];
signed main() {
	freopen("line.in","r",stdin);
	freopen("line.out","w",stdout);
	ios::sync_with_stdio(false);
	cin.tie(0),cout.tie(0);
	cin>>n;
	for(int i=1; i<n; i++) {
		int x,y,z;
		cin>>x>>y>>z;
		a[x][y]=a[y][x]=z;
	}
	while(1) {
		int the_main_max=0;
		pair<int,int> the_end_first_x_and_y,the_end_second_x_and_y;
		pair<int,int> the_first_x_and_y,the_second_x_and_y;
		for(int i=1; i<=n; i++) {
			int maxn_first=0,maxn_second=0;
			for(int j=1; j<=n; j++) {
				if(maxn_first<=a[i][j]) {
					maxn_first=a[i][j];
					the_first_x_and_y.first=i;
					the_first_x_and_y.second=j;
				}
			}
			for(int j=1; j<=n; j++) {
				if(maxn_first!=a[i][j]) {
					if(maxn_second<=a[i][j]) {
						maxn_second=a[i][j];
						the_second_x_and_y.first=i;
						the_second_x_and_y.second=j;
					}
				}
			}
			if(the_first_x_and_y.first==the_second_x_and_y.first&&point[the_second_x_and_y.first]){
				maxn_first=0;
			}
			if(the_first_x_and_y.first==the_second_x_and_y.second&&point[the_second_x_and_y.second]){
				maxn_first=0;
			}
			if(the_first_x_and_y.second==the_second_x_and_y.first&&point[the_second_x_and_y.first]){
				maxn_first=0;
			}
			if(the_first_x_and_y.second==the_second_x_and_y.second&&point[the_second_x_and_y.second]){
				maxn_first=0;
			}
			if(maxn_first!=0&&maxn_second!=0) {
				if(the_main_max<=maxn_first+maxn_second) {
					the_main_max=maxn_first+maxn_second;
					the_end_first_x_and_y=the_first_x_and_y;
					the_end_second_x_and_y=the_second_x_and_y;
				}
			}
		}
		if(the_main_max==0) {
			break;
		} else {
			ans+=the_main_max;
			a[the_end_first_x_and_y.first][the_end_first_x_and_y.second]=0;
			a[the_end_first_x_and_y.second][the_end_first_x_and_y.first]=0;
			a[the_end_second_x_and_y.first][the_end_second_x_and_y.second]=0;
			a[the_end_second_x_and_y.second][the_end_second_x_and_y.first]=0;
			if(the_end_first_x_and_y.first==the_end_second_x_and_y.second){
				point[the_end_first_x_and_y.first]=true;
			}
			if(the_end_first_x_and_y.first==the_end_second_x_and_y.first){
				point[the_end_first_x_and_y.first]=true;
			}
			if(the_end_first_x_and_y.second==the_end_second_x_and_y.second){
				point[the_end_first_x_and_y.second]=true;
			}
			if(the_end_first_x_and_y.second==the_end_second_x_and_y.first){
				point[the_end_first_x_and_y.second]=true;
			}
		}
	}
	cout<<ans;
	return 0;
}
/*
5
1 2 10
1 3 40
1 4 15
1 5 20
*/