#include <stdio.h>#include <string.h>#define INF 100000000int map[101][101];int dis[101];int vis[101];int n;long long ans = 0;void prim(){    int i,j;    int min,pos;    memset(vis,0,sizeof(vis));    memset(dis,INF,sizeof(INF));    vis[1] = 1;    dis[1] = 0;    for(i = 1;i<=n;i++)    {        dis[i] = map[1][i];    }    min = INF;    for(i = 1;i<=n-1;i++)    {        min = INF;        for(j = 1;j<=n;j++)        {            if(!vis[j] && dis[j]<min)            {                pos = j;                min = dis[j];            }        }        vis[pos] = 1;        ans = ans + min;        for(j = 1;j<=n;j++)        {            if(!vis[j] && dis[j]>map[pos][j])            dis[j] = map[pos][j];        }    }}int main(){    int i,j;    int u,v,w;    while(scanf("%d",&n),n)    {        for(i = 1;i<=n;i++)        {            for(j = 1;j<=n;j++)            {                if(i == j)                map[i][j] = 0;                else                map[i][j] = INF;            }        }        for(i = 1;i<=(n*(n-1))/2;i++)        {            scanf("%d%d%d",&u,&v,&w);            {                if(map[u][v]>w)                {                    map[u][v] = map[v][u] = w;                }            }        }        prim();        printf("%lld\n",ans);        ans = 0;    }}