#include <fstream>
#include <vector>
#include <algorithm>
#include <queue>
#define NMAX 200003
using namespace std;

int tati[NMAX+3],n,m;
int cost=0;
bool viz[400003];
int d[NMAX+3];

struct val{
   int vecin,cost;

};
vector<val> graf[NMAX+1];

struct cmp{
  bool operator() (const val& st, const val&dr) const
  {
    return st.cost>dr.cost;
  }
};

priority_queue<val,vector<val>,cmp> q;


ifstream fin ("apm.in");
ofstream fout ("apm.out");

int ct=0;

int cRad(int nr)
{
    int k=nr;
    while(tati[k]>0)
    {
        k=tati[k];
    }
    return k;
}

int main()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        int x,y,cost;
        fin>>x>>y>>cost;
        graf[x].push_back({y,cost});
        graf[y].push_back({x,cost});
    }
    for(int i=1; i<=n; i++)
    {
        d[i]=2000005;
    }
    d[1]=0;
    q.push({1,0});
    while(!q.empty())
    {
       val nd=q.top();
       int nod=nd.vecin;
       if(viz[nod]==1)
       {
           q.pop();
           continue;
       }
       viz[nod]=1;
       ct+=nd.cost;
       for(int i=0; i<graf[nod].size(); i++)
       {
           int vc=graf[nod][i].vecin;
           int cs=graf[nod][i].cost;
           if(!viz[vc] && d[vc]>cs)
           {
               q.push({vc,cs});
               d[vc]=cs;
               tati[vc]=nod;
           }
       }
    }
    fout<<ct<<"\n"<<n-1<<"\n";
    for(int i=2; i<=n; i++)
    {
        fout<<i<<" "<<tati[i]<<"\n";
    }
    return 0;
}