#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;

struct cmp
{
    bool operator() (const pair<pair<int,int>,int > &l, const pair<pair<int,int>,int > &r)
    {
        return l.second>r.second;
    }
};
int n,m,viz[100001];
priority_queue<pair<pair<int,int>,int >,vector<pair<pair<int,int>,int > >, cmp> Q;
vector<pair<int,int> > G;
int main()
{
    ifstream fin("apm.in");
    ofstream fout("apm.out");
    fin>>n>>m;
    vector<pair<int,int> > g[n+1];
    int a,b,c;
    for(int i=1;i<=m;i++)
    {
        fin>>a>>b>>c;
        g[a].push_back(make_pair(b,c));
        g[b].push_back(make_pair(a,c));
    }
    int cont=0,c2=0;
    Q.push(make_pair(make_pair(1,1),0));
    while(!Q.empty())
    {
        pair<int,int> p=Q.top().first;
        int nod=p.second;
        if(!viz[nod])
        {
            viz[nod]=1;
            cont++;
            c2+=Q.top().second;
            Q.pop();
            G.push_back(make_pair(p.first,p.second));
            for(int i=0;i<g[nod].size();++i)
            {
                int vecin=g[nod][i].first;
                int cost=g[nod][i].second;
                if(!viz[vecin])
                    Q.push(make_pair(make_pair(nod,vecin),cost));
            }
        }
        else Q.pop();
        if(cont==n) break;
    }
    fout<<c2<<'\n'<<n-1<<'\n';
    for(int i=1;i<G.size();i++)
        fout<<G[i].first<<" "<<G[i].second<<'\n';
    return 0;
}