#include<stdio.h>

#include<algorithm>

using namespace std;

struct dis

{

        int a, b, c;

} s[];

int cmp(dis x, dis y)

{

        return x.c < y.c;

}

int father[];

int fsize[];

int findfather(int y)

{

        int r = y;

        while (r != father[r])

        {

                r = father[r];

        }

        return r;

}

int combine(int a, int b)

{

        int fx = findfather(a);

        int fy = findfather(b);

        if (fx != fy)

        {

                if (fsize[fx] >= fsize[fy])

                {

                        father[fy] = fx;

                        fsize[fx] += fsize[fy];

                        fsize[fy] = ;

                }

                else

                {

                        father[fx] = fy;

                        fsize[fy] += fsize[fx];

                        fsize[fx] = ;

                }

                return ;

        }

        else

        {

                return ;

        }

}

int main()

{

        int t, i, n, sum, m;

        while (~scanf("%d", &t), t)

        {

                n = t * (t - ) / ;

                for (i = ; i <= t; i++)

                {

                        fsize[i] = ;

                        father[i] = i;

                }

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

                {

                        scanf("%d%d%d", &s[i].a, &s[i].b, &s[i].c);

                }

                sort(s, s + n, cmp);

                m = , sum = ;

                for (i = ; i < n && m < t; i++)

                {

                        if (combine(s[i].a, s[i].b))

                        {

                                m++;

                                sum += s[i].c;

                        }

                }

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

        }

        return ;

}