#include <iostream>
#include <fstream>
#include <set>
#include <vector>
#include <queue>

using namespace std;

const int nMax = 200005;

int n, m;
vector<pair<int, int> > vecini[nMax];
bool added[nMax];
vector<pair<int, int> > ans;
int ansCost;

void citire()
{
    ifstream in("apm.in");
    in >> n >> m;
    int x, y, c;
    for(int i = 1; i <= m; ++i)
    {
        in >> x >> y >> c;
        vecini[x].push_back(make_pair(c, y));
        vecini[y].push_back(make_pair(c, x));
    }
    in.close();
}

void rezolvare()
{
    typedef pair<int, pair<int, int> > triple;
    priority_queue<triple, vector<triple>, greater<triple> > s;
    added[1] = true;
    for(auto v:vecini[1])
        s.push(make_pair(v.first, make_pair(1, v.second)));
    pair<int, pair<int, int> > p;
    while(s.empty() == false)
    {
        while(s.empty() == false && added[s.top().second.second] == true)
            s.pop();
        if(s.empty() == false)
        {
            p = s.top();
            ansCost += p.first;
            ans.push_back(p.second);
            added[p.second.second] = true;

            for(const auto &v:vecini[p.second.second])
                if(added[v.second] == false)
                    s.push(make_pair(v.first, make_pair(p.second.second, v.second)));
        }
    }
}

void afisare()
{
    ofstream out("apm.out");
    out << ansCost << "\n" << n-1 << "\n";
    for(auto x:ans)
        out << x.first << " " << x.second << "\n";
    out.close();
}

int main()
{
    citire();
    rezolvare();
    afisare();
    return 0;
}