#include <stdio.h>
#include <string.h>
#include <stdlib.h>

using namespace std;

#define MAXN 1024
#define MAXM 2000002
#define MIN(a,b) ((a<b)?a:b)

int adj[MAXN][MAXN];
int d[MAXN];

int main (void)
{
    int n, m, x, y, z, inst = 0;
    long long custo;

    while (scanf ("%d %d", &n, &m) == 2)
    {
        custo = 0;

        for (int i = 0; i < n; i++)
        {
            for (int j = 0; j < n; j++)
            {
                adj[i][j] = 0x3f3f3f3f;
            }
        }

        for (int i = 0; i < m; i++)
        {
            scanf ("%d %d %d", &x, &y, &z);
            x--; y--;
            adj[x][y] = MIN(z, adj[x][y]);
            adj[y][x] = adj[x][y];
        }

        int count = 1;
        for (int i = 0; i < n; i++)
        {
            d[i] = adj[0][i];
        }
        d[0] = 0;

        while (count < n)
        {
            int menor = 0x3f3f3f3f, j;
            for (int i = 0; i < n; i++)
            {
                if (d[i] && d[i] < menor)
                {
                    j = i;
                    menor = d[i];
                }
            }

            custo += d[j];
            d[j] = 0;

            for (int i = 0; i < n; i++)
            {
                if (adj[j][i] < d[i])
                    d[i] = adj[j][i];
            }

            count++;
        }

        printf ("Instancia %d\n%lld\n\n", ++inst, custo);
    }

    return 0;
}