#include <fstream>
#include <set>
#include <vector>
#include <bitset>
#define inf 2000000000
using namespace std;
ifstream fin ("apm.in");
ofstream fout ("apm.out");
int n,m,x,y,sum,c,i,d[200001],t[200001];
vector < pair <int,int> > v[200001];
set < pair <int,int> > s;
bitset <200001> viz;
int main()
{
    fin>>n>>m;
    for (i=1; i<=m; i++)
    {
        fin>>x>>y>>c;
        v[x].push_back (make_pair (y,c));
        v[y].push_back (make_pair (x,c));
    }
    for (i=1; i<=n; i++)
        d[i]=inf;
    d[1]=0;
    t[1]=-1;
    s.insert (make_pair (0,1));
    while (!s.empty ())
    {
        int nod=s.begin ()->second;
        s.erase (s.begin ());
        if (viz[nod]==1)
            continue;
        viz[nod]=1;
        for (i=0; i<v[nod].size (); i++)
        {
            int cost=v[nod][i].second;
            int vecin=v[nod][i].first;
            if (viz[vecin]==0&&d[vecin]>cost)
            {
                s.insert ({cost,vecin});
                d[vecin]=cost;
                t[vecin]=nod;
            }
        }
    }
    for (i=1; i<=n; i++)
        sum+=d[i];
    fout<<sum<<"\n"<<n-1<<"\n";
    for (i=2; i<=n; i++)
        fout<<t[i]<<" "<<i<<"\n";
    return 0;
}