#include<fstream>
#include<queue>
#include<vector>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
int viz[200005],n,m,nrm,rez[2][200005];
long long cost;
struct muchie{int x,y;
              long long co;};
vector<muchie>v[200005];
struct comp
{
    bool operator()(muchie a,muchie b)
    {
        return a.co>b.co;
    }
};
priority_queue<muchie,vector<muchie>,comp>q;

void citire()
{
    muchie aux;
    int x,y;
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y>>aux.co;
        aux.x=x; aux.y=y;
        v[x].push_back(aux);
        swap(aux.x,aux.y);
        v[y].push_back(aux);
    }
}

void prim()
{
    muchie aux;
    for(int i=0;i<v[1].size();i++)
        q.push(v[1][i]);
    viz[1]=1;
    while(!q.empty())
    {
        aux=q.top(); q.pop();
        if(viz[aux.y]==0)
        {
            viz[aux.y]=1; cost+=aux.co; nrm++;
            rez[0][nrm]=aux.x; rez[1][nrm]=aux.y;
            for(int i=0;i<v[aux.y].size();i++)
                q.push(v[aux.y][i]);
        }
    }
}

void afis()
{
    fout<<nrm<<'\n'<<cost<<'\n';
    for(int i=1;i<=nrm;i++)
        fout<<rez[0][i]<<" "<<rez[1][i]<<'\n';
}

int main()
{
    citire();
    prim();
    afis();
    fin.close();
    fout.close();
    return 0;
}