#include<vector>
#include<algorithm>
#include <fstream>
#include <iostream>
#define maxim 200000
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
int n,m,x,y,c,nr,a[maxim];
std::vector <int> vect[maxim],vect1[maxim];
std::vector <pair<int,pair<int,int> > > vact;
std::vector <pair<int,int> > vuct;
int main()
{
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>y>>c;
        vect[x].push_back(y);
        vect[y].push_back(x);
        vact.push_back(make_pair(c,make_pair(x,y)));
    }
     for(int i=1;i<=n;i++)
        a[i]=i;
    sort(vact.begin(),vact.end());
    int s=0;
    for(int i=0;i<m;i++)
    {
       x=vact[i].second.first;
       y=vact[i].second.second;
       if(a[x]!=a[vact[i].second.second])
       {
           s=s+vact[i].first;
           if(a[x]<a[y])
           a[y]=a[x];
           else
           a[x]=a[y];
           vect1[x].push_back(y);
           vuct.push_back(make_pair(x,y));
           vect1[y].push_back(x);
           for(int j=0;j<vect1[vact[i].second.second].size();j++)
            a[vect1[y][j]]=a[x];
       }
    }
    fout<<s;
    fout<<"\n"<<vuct.size();
    for(int i=0;i<vuct.size();i++)
        fout<<"\n"<<vuct[i].first<<"  "<<vuct[i].second;
    return 0;
}