#include <iostream>
#include <fstream>
#include <algorithm>
#include <vector>
using namespace std;

ifstream fin ("apm.in");
ofstream fout ("apm.out");

vector <pair <int, int>> v[200001];
bool viz[200001];
int c[200001];
int p[200001];

int main()
{
    int n, m, i, j, x, y, z, nrsol;
    int rasp;

    fin >> n >> m;
    for (i = 1; i<=m; i++)
    {
        fin >> x >> y >> z;
        v[x].push_back ({y, z});
        v[y].push_back ({x, z});
    }
    for (i = 1; i<=n; i++)
        c[i] = 1000000000;
    c[1] = 0;
    viz[1] = 1;
    for (i = 0; i<v[1].size(); i++)
    {
        c[v[1][i].first] = min (c[v[1][i].first], v[1][i].second);
        p[v[1][i].first] = 1;
    }

    rasp = 0;
    for (i = 1; i<=n-1; i++)
    {
        x = 0;
        y = 1000000000;
        for (j = 1; j<=n; j++)
            if (viz[j] == 0)
            {
                if (c[j] < y)
                {
                    x = j;
                    y = c[j];
                }
            }

        viz[x] = 1;
        rasp = rasp + y;
        for (j = 0; j<v[x].size(); j++)
            if (viz[v[x][j].first] == 0)
            {
                if (v[x][j].second < c[v[x][j].first])
                {
                    c[v[x][j].first] = v[x][j].second;
                    p[v[x][j].first] = x;
                }
            }
    }
    fout << rasp << '\n';
    fout << n-1 << '\n';
    for (i = 2; i<=n; i++)
        fout << i << ' ' << p[i] << '\n';
    return 0;
}