#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>

using namespace std;
ifstream in("apm.in");
ofstream out("apm.out");
int p[200001], n, m;
pair<pair<int, int>, int> muchii[400001];
long long cost_minim;
vector<pair<int, int> > muchiiapm;

bool cmp(pair<pair<int, int>, int> muchie1, pair<pair<int, int>, int> muchie2){
    return muchie1.second < muchie2.second;
}

int parinte(int nod1){
    while(p[nod1] != 0){
        nod1 = p[nod1];
    }
    return nod1;
}

int main()
{
    int x, y, c;
    in >> n >> m;
    for(int i = 1; i <= m; i++){
        in >> x >> y >> c;
        muchii[i] = {{x, y}, c};
    }
    sort(muchii + 1, muchii + m + 1, cmp);
    for(int i = 1; i <= m; i++){
        if(parinte(muchii[i].first.first) != parinte(muchii[i].first.second)){
            muchiiapm.push_back({muchii[i].first.first, muchii[i].first.second});
            cost_minim += muchii[i].second;
            p[max(parinte(muchii[i].first.first), parinte(muchii[i].first.second))] = min(parinte(muchii[i].first.first), parinte(muchii[i].first.second));
        }
    }
    out << cost_minim << '\n';
    out << muchiiapm.size() << '\n';;
    for(int i = 0; i < muchiiapm.size(); i++){
        out << muchiiapm[i].first << " " << muchiiapm[i].second<< '\n';
    }
    return 0;
}