#include <fstream.h>     
#define NMAX 200001
#define MMAX 400001
ifstream f("apm.in");
ofstream g("apm.out");
int n,m,L[NMAX];
struct muchie{int x,y,c;};
muchie u[MMAX],v[MMAX];

int divide(int s, int d)
{int aux, i=s, j=d, pi=0, pj=1;
 muchie aux1;
 while(i<j)
  {if(u[i].c>u[j].c) {aux1=u[i]; u[i]=u[j]; u[j]=aux1; aux=pi; pi=pj; pj=aux;}
   i+=pi; j-=pj;                     
  }    
 return i;
}   
  
void init()    
{for (int i=1;i<=n;i++) L[i]=i;   
}

int parinte(int p)
{while(L[p]!=p)
  p=L[p];
 return p;
}

void citire()
{int i,x,y,c; f>>n>>m;
  for(i=1;i<=m;i++) {f>>x>>y>>c; u[i].x=x; u[i].y=y; u[i].c=c;}
  f.close();
}

void sortare(int s, int d)
{int m;
 if(s<d) {m=divide(s,d); sortare(s, m-1); sortare(m+1, d);}
}

int main()
{int i=1,j,k=0,x,y;
 long long ct=0;
 citire();
 sortare(1, m);
 init();
 while(k<n-1)
  {x=parinte(u[i].x);
   y=parinte(u[i].y);
   if(x!=y)
    {k++; ct=ct+u[i].c;
     v[k]=u[i];
     L[parinte(u[i].y)]=x;
    }
   i++;     
  }     
 g<<ct<<'\n'<<n-1<<'\n';     
 for(i=1; i<n; i++)     
  g<<v[i].x<<' '<<v[i].y<<'\n';     
 g.close(); f.close();     
 return 0;     
}