#include <cstdio>
#include <algorithm>
#define MAX 110

using namespace std ;
int f[MAX] ;
struct Edge{
	int x , y , w ;
}edge[MAX*MAX];

void init()
{
	for(int i = 0 ; i < MAX ; ++i)
	{
		f[i] = i ;
	}
}

int find(int x)
{
	int r = x ;
	while(r != f[r] )
	{
		r = f[r] ;
	}
	int temp ;
	while(x != f[x])
	{
		temp = f[x] ;
		f[x] = r ;
		x = temp ;
	}
	return r ;
}

bool cmp(const Edge &e1 , const Edge &e2)
{
	return e1.w<e2.w ;
}

int kruskal(int n)
{
	sort(edge,edge+n,cmp);
	int sum = 0 ;
	init() ;
	for(int i = 0 ; i < n ; ++i)
	{
		int x = find(edge[i].x) , y = find(edge[i].y) ;
		if(x != y)
		{
			sum += edge[i].w ;
			f[x] = y ;
		}
	}
	return sum ;
}

int main()
{
	int n;
	while(~scanf("%d",&n) && n)
	{
		int m = (n*(n-1))/2 ;
		for(int i = 0 ; i < m ; ++i)
		{
			scanf("%d%d%d",&edge[i].x,&edge[i].y,&edge[i].w) ;
		}
		int sum = kruskal(m) ;
		printf("%d\n",sum);
	}
	return 0 ;
}