#include<fstream>
#include<algorithm>
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
int i,n,m,k,s,t[200100];
struct muchie{int x,y,c;};
muchie v[400100],sol[200100];
inline bool cmp(muchie a,muchie b)
{
    return a.c<b.c;
}
inline int tata(int x)
{
    if(t[x]==x)
    return x;
    return t[x]=tata(t[x]);
}
int main()
{
    f>>n>>m;
    for(i=1;i<=m;++i)
    {
        f>>v[i].x>>v[i].y>>v[i].c;
    }
    for(i=1;i<=n;++i)
    t[i]=i;
    sort(v+1,v+m+1,cmp);
    for(i=1;i<=m;++i)
    if(tata(v[i].x)!=tata(v[i].y))
    {
        t[t[v[i].x]]=t[v[i].y];
        ++k;
        sol[k]=v[i];
        s+=v[i].c;
    }
    g<<s<<'\n'<<n-1<<'\n';
    for(i=1;i<n;++i)
    g<<sol[i].y<<' '<<sol[i].x<<'\n';
    return 0;
}