#include <fstream>
#include <algorithm>
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
struct el{int x,y,c;}v[1<<18];
int i,n,m,t,S,sol[1<<18],GR[1<<18];
struct cmp
{
    bool operator () (el a,el b)
    {
        return a.c<b.c;
    }
};
inline int gr(int i)
{
    if(GR[i]==i) return i;
    GR[i]=gr(GR[i]);
    return GR[i];
}
inline void unite(int i,int j)
{
    GR[gr(i)]=gr(j);
}
int main ()
{
    f>>n>>m;
    for(i=1;i<=m;++i)
        f>>v[i].x>>v[i].y>>v[i].c;
    sort(v+1,v+m+1,cmp());
    for(i=1;i<=n;++i) GR[i]=i;
    for(i=1;i<=m;++i)
        if(gr(v[i].x)!=gr(v[i].y))
        {
            S+=v[i].c;
            unite(v[i].x,v[i].y);
            sol[++t]=i;
        }
    g<<S<<'\n'<<n-1<<'\n';
    for(i=1;i<n;++i)
        g<<v[sol[i]].x<<' '<<v[sol[i]].y<<'\n';
    return 0;
}