#include <bits/stdc++.h>

using namespace std;

ifstream f ("apm.in");
ofstream g ("apm.out");

const int nmax = 2e5 + 1;

int rin[nmax];

struct Graf
{
    int x, y, cost;
};
Graf v[nmax], rasp[nmax];

bool Compara(Graf a, Graf b)
{
    return a.cost < b.cost;
}

int Serif(int i)
{
    if(rin[i] == i)
        return i;

    return rin[i] = Serif(rin[i]);
}

int main()
{
    int n, m, cnt = 0, k = 0;

    f >> n >> m;

    for(int i = 1; i <= m; ++i)
        f >> v[i].x >> v[i].y >> v[i].cost;

    for(int i = 1; i <= n; ++i)
        rin[i]=i;

    sort(v + 1, v + m + 1, Compara);

    for(int i = 1; i <= m; ++i)
    {
        if(Serif(v[i].x) != Serif(v[i].y))
        {
            rin[Serif(v[i].y)] = v[i].x;
            cnt += v[i].cost;
            rasp[++k].x = v[i].x;
            rasp[k].y = v[i].y;
        }
    }

    g<<cnt<<'\n';
    g<<k<<'\n';

    for(int i = 1; i <= k; ++i) // am pus < k in loc de <= k ...
        g<<rasp[i].x<<" "<<rasp[i].y<<'\n';
    return 0;
}