#include <bits/stdc++.h>
using namespace std;

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

struct Muchie
{
    int x, y, c;
    bool operator<(const Muchie e)const
    {
        return c < e.c;
    }
};

int n, m;
int t[200005];
Muchie a[400005];
queue<pair<int, int>> sol;

int FindRoot(int x)
{
    int y, rad = x;
    while (t[rad] != 0)
        rad = t[rad];
    while (x != rad)
    {
        y = t[x];
        t[x] = rad;
        x = y;
    }
    return rad;
}
void Union(int x, int y)
{
    t[y] = x;
}

int main()
{   
    int i, x, y, c, cost;
    fin >> n >> m;
    for (i = 1; i <= m; i++)
        fin >> a[i].x >> a[i].y >> a[i].c;

    cost = 0;
    sort(a + 1, a + m + 1);
    for (i = 1; i <= m; i++)
    {
        x = a[i].x; y = a[i].y; c = a[i].c;
        x = FindRoot(x); y = FindRoot(y);
        if (x != y)
        {
            cost += c;
            Union(x, y);
            sol.push({a[i].x, a[i].y});
        }
    }
    fout << cost << "\n" << sol.size() << "\n";
    while (!sol.empty())
    {
        fout << sol.front().first << " " << sol.front().second << "\n";
        sol.pop();
    }
}