#include <bits/stdc++.h>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");

int n, m, t[200001], nr, k;
pair<int, int> v[400001];

struct muchie
{
    int x, y, c;
    bool operator < (muchie m) const
    {
        return c < m.c;
    }
}a[400001];

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

int Find(int x)
{
    int y;
    if (t[x] == 0)
        return x;
    y = Find(t[x]);
    t[x] = y;
    return y;
}

int main()
{
    int i, x, y, cost = 0;
    fin >> n >> m;
    nr = n;
    for (i = 1 ; i <= m ; i++)
        fin >> a[i].x >> a[i].y >> a[i].c;
    sort(a + 1, a + m + 1);
    for (i = 1; i <= m && nr > 1 ; i++)
    {
        x = Find(a[i].x);
        y = Find(a[i].y);
        if (x != y)
        {
            --nr;
            Union(x, y);
            cost += a[i].c;
            v[++k] = {a[i].x, a[i].y};
        }
    }
    fout << cost << "\n";
    fout << k << "\n";
    for (i = 1 ; i <= k ; i++)
        fout << v[i].first << " " << v[i].second << "\n";
    return 0;
}