#include <iostream>

 #include <cstring>

 #include <cstdio>

 #include <cmath>

 #include <cctype>

 #include <algorithm>

 #include <numeric>

 #define typec int

 using namespace std;

 const int V = ;

 const int inf = 0xffff;

 int vis[V]; typec lowc[V], Map[V][V];

 typec prim (typec cost[][V], int n) {

     int i, j, p;

     typec minc, res = ;

     memset(vis, , sizeof(vis));

     vis[] = ;

     for (int i = ; i < n; ++ i) lowc[i] = cost[][i];

     for (int i = ; i < n; ++ i) {

         minc = inf; p = -;

         for (j = ; j < n; ++ j) {

             if ( == vis[j] && minc > lowc[j]) {

                 minc = lowc[j]; p = j;

             }

         }

         if (inf == minc) return -;

         res += minc; vis[p] = ;

         for (j = ; j < n; ++ j) {

             if ( == vis[j] && lowc[j] > cost[p][j])

             lowc[j] = cost[p][j];

         }

     }

     return res;

 }

 int main () {

     int n;

     while (~scanf("%d", &n) && n) {

         for (int i = ; i < V; ++ i) {

             for (int j = ; j < V; ++ j) {

                 if (i == j) Map[i][j] = ;

                     else Map[i][j] = inf;

             }

         }

         for (int i = ; i < n * (n - ) / ; ++i) {

             int x, y, c; scanf("%d%d%d", &x, &y, &c);

             if (x == y) continue;

             Map[x - ][y - ] = Map[y - ][x - ] = min(Map[x - ][y - ], c);

         }

         cout << prim(Map, n) << endl;

     }

     return ;

 }