#include <iostream>
#include <fstream>
#include <algorithm>

using namespace std;

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

struct muchie
{
    int x, y, c; /// muchia (x,y) de cost c
    bool ales; /// ales = true daca muchia este in APM

    bool operator< (const muchie A) const
    {
        return c < A.c;
    }
};
muchie a[400002];
int n, m, t[200002], costMin;

void Union(int x, int y)
{
    t[x] = y;
}

/// ret. radacina c.c. din care face parte nodul x
int Find(int x)
{
    int rad, y;
    rad = x;
    while (t[rad] != 0)
        rad = t[rad];
    /// comprimam drumurile, adica toate nodurile
    /// din traseul de la x la rad se leaga direct de rad
    while (x != rad)
    {
        y = t[x];
        t[x] = rad;
        x = y;
    }
    return rad;
}

void Citire()
{
    int i;
    fin >> n >> m;
    for (i = 1; i <= m; i++)
        fin >> a[i].x >> a[i].y >> a[i].c;
}

/// O(m log m + m log*m)
void Kruskal()
{
    int i, x, y, nrcc;
    sort(a + 1, a + m + 1);
    nrcc = n;
    for (i = 1; i <= m && nrcc > 1; i++)
    {
        x = Find(a[i].x);
        y = Find(a[i].y);
        if (x != y)
        {
            Union(x, y);
            nrcc--;
            a[i].ales = true;
            costMin += a[i].c;
        }
    }
    fout << costMin << "\n";
    fout << (n - 1) << "\n";
    for (i = 1; i <= m; i++)
        if (a[i].ales) fout << a[i].x << " " << a[i].y << "\n";
}

int main()
{
    Citire();
    Kruskal();
    fout.close();
    return 0;
}