#include<fstream>
#include<algorithm>
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
int n,m,i,xx,yy,s,k;
int tata[200005],rg[200001],fin[200001];
struct muchie
{
    int x,y,c;
}a[200001];
bool cmp(muchie nr1,muchie nr2)
{
    return nr1.c<nr2.c;
}
int radacina(int nr)
{
    while(nr!=tata[nr])
      nr=tata[nr];
    return nr;
}
void adauga(int xx,int yy)
{
    if(rg[xx]>rg[yy])
      tata[yy]=xx;
    else
      tata[xx]=yy;
    if(rg[xx]==rg[yy])
      rg[yy]++;
}
int main()
{
    f>>n>>m;
    for(i=1;i<=n;i++)
    {
        tata[i]=i;
        rg[i]=1;
    }
    for(i=1;i<=m;i++)
      f>>a[i].x>>a[i].y>>a[i].c;
    s=0;
    sort(a+1,a+m+1,cmp);
    for(i=1;i<=m;i++)
    {
        xx=radacina(a[i].x);
        yy=radacina(a[i].y);
        if(xx!=yy)
        {
            k++;
            fin[k]=i;
            s+=a[i].c;
            adauga(xx,yy);
        }
    }
    g<<s<<"\n";
    g<<k<<"\n";
    for(i=1;i<=k;i++)
      g<<a[fin[i]].x<<" "<<a[fin[i]].y<<"\n";
    return 0;
}