#include <bits/stdc++.h>

using namespace std;

struct edge{
    int x, y, c;
    bool operator<(const edge &obj)const{
        return c < obj.c;
    }
};

int n, m;
bool ok[200005];
multiset<edge> q;
vector<edge> v[200005], sol;

edge make_edge(int x, int y, int c)
{
    edge aux;
    aux.x = x;
    aux.y = y;
    aux.c = c;
    return aux;
}

int main()
{
    ifstream fin ("apm.in");
    ofstream fout ("apm.out");
    fin >> n >> m;
    for (int i = 1; i <= m; ++i){
        int x, y, z;
        fin >> x >> y >> z;
        v[x].push_back(make_edge(x, y, z));
        v[y].push_back(make_edge(x, y, z));
    }
    for (vector<edge>::iterator it = v[1].begin(); it != v[1].end(); ++it)
        q.insert(*it);
    int apm = 0;
    for (int t = 1; t < n; ++t){
        while(ok[q.begin()->x] && ok[q.begin()->y])
            q.erase(q.begin());
        int x = q.begin()->x, y = q.begin()->y, c = q.begin()->c;
        sol.push_back(*q.begin());
        apm += c;
        q.erase(q.begin());
        if(!ok[x]){
            for (vector<edge>::iterator it = v[x].begin(); it != v[x].end(); ++it)
                q.insert(*it);
        }
        if(!ok[y]){
            for (vector<edge>::iterator it = v[y].begin(); it != v[y].end(); ++it)
                q.insert(*it);
        }
        ok[x] = ok[y] = 1;
    }
    fout << apm << "\n" << n-1 << "\n";
    for (int i = 0; i < n-1; ++i)
        fout << sol[i].x << " " << sol[i].y << "\n";
    return 0;
}