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

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

struct Trei
{
    int x, y, c, v;
    bool operator<(const Trei e) const
    {
        return c < e.c;
    }
} a[400005];

int Total;
int n, m;
vector<pair<int,int>> sol;
int t[200005];

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

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


int main()
{
    int i, x, y;
    fin >> n >> m;
    for(i=1;i<=m;i++)
        fin >> a[i].x >> a[i].y >> a[i].c;
    sort(a + 1, a + m + 1);
    int nrc = n;
    for(i=1;i<=m && nrc > 1;i++)
    {
        x = FindRoot(a[i].x);
        y = FindRoot(a[i].y);
        if(x != y)
        {
            Union(x, y);
            a[i].v = 1;
            Total += a[i].c;
            sol.push_back({a[i].x,  a[i].y});
            nrc--;
        }
    }
    fout << Total << "\n";
    fout << sol.size() << "\n";
    for(auto w : sol)
        fout << w.first << " " << w.second << "\n";
    return 0;
}