#include<fstream>
#include<algorithm>
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
int tata[200005],niv[200005],fin[200005],rez,k;
int n,m,i,xx,yy;
struct muchie
{
    int x,y,c;
}a[200005];//muchiile in care retin costul muchiei(c) si nodurile legate de aceasta(x-y)
bool cmp(muchie nr1,muchie nr2)
{
    return nr1.c<nr2.c;
}
int radacina(int nr)//caut radacina nodului nr
{
    while(tata[nr]!=nr)
      nr=tata[nr];
    return nr;
}
void add(int xx,int yy)//adaug o muchie in arbore
{
    if(niv[xx]>niv[yy])//vector de tati completat in functie de nivel(if + else)
      tata[yy]=xx;
    else
      tata[xx]=yy;
    if(niv[xx]==niv[yy])//actualizez nivelul
      niv[yy]++;
}
int main()
{
    f>>n>>m;
    for(i=1;i<=n;i++)//initializez vectorul de tati si pentru nivele
    {
        niv[i]=1;
        tata[i]=i;
    }
    for(i=1;i<=m;i++)//retin muchiile
      f>>a[i].x>>a[i].y>>a[i].c;
    rez=0;
    sort(a+1,a+m+1,cmp);//sortez muchiile crescator dupa costul acestora
    for(i=1;i<=m;i++)//iau fiecare muchie pe rand
    {
        xx=radacina(a[i].x);//retin radacinile nodurilor legate de muchie
        yy=radacina(a[i].y);
        if(xx!=yy)//au radacini diferite => adaug muchia
        {
            k++;
            fin[k]=i;
            rez+=a[i].c;
            add(xx,yy);
        }
    }
    g<<rez<<"\n";
    g<<k<<"\n";
    for(i=1;i<=k;i++)
      g<<a[fin[i]].x<<" "<<a[fin[i]].y<<"\n";
    return 0;
}