#include <iostream>

 #include <stdio.h>

 #include <queue>

 using namespace std;

 const int N = ;

 const int inf = (int)1e9;

 int g[N][N];

 bool vis[N];

 int dis[N];

 struct node{

     int loc;

     int w;

     bool friend operator<(const node& a,const node& b){

         return a.w > b.w;

     }

 };

 priority_queue<node > que;

 void init(int& n){

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

         dis[i] = inf;

         vis[i] = ;

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

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

             else g[i][j] = inf;

     }

 }

 int prime(int& n){

     while(!que.empty()) que.pop();

     que.push(node{,});

     dis[] = ;

     int u;

     while(!que.empty()){

         u = que.top().loc;

         que.pop();

         vis[u] = ;

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

             if(!vis[v] && dis[v] > g[u][v]){

                 dis[v] = g[u][v];

                 que.push(node{v,dis[v]});

             }

         }

     }

     int ans = ;

     for(int i = ; i <= n; i++) ans += dis[i];

     return ans;

 }

 int main(){

     int n;

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

         int u,v,w;

         int len = n*(n-)/;

         init(n);

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

             scanf("%d%d%d",&u,&v,&w);

             if(g[u][v] > w)

                 g[u][v] = g[v][u] = w;

         }

         printf("%d\n",prime(n));

     }

     return ;

 }