#include <fstream>
#include <queue>
#define f first
#define s second
using namespace std;

ifstream fin ("apm.in");
ofstream fout ("apm.out");

int n, m, tot, viz[200005], x, y, c, nrm, p[200005];
vector < pair <int, int> > v[200005];
priority_queue < pair <int, pair <int, int> >, vector <pair <int, pair <int, int> > >, greater < pair <int, pair <int, int> > >  > pq;
pair <int, int> mini;

int main()
{
    int i;

    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));
    }

    viz[1]=1;
    for (auto it: v[1])
    {
        pq.push(make_pair(it.s, make_pair(1, it.f)));
    }

    tot=0;
    nrm=n-1;
    while (pq.empty()==0)
    {
        mini=pq.top();
        pq.pop();

        if (viz[mini.s.s]==0)
        {
            viz[mini.s.s]=1;
            tot=tot+mini.f;
            p[mini.s.s]=mini.s.f;

            for (auto it: v[mini.s.s])
            {
                pq.push(make_pair(it.s, make_pair(mini.s.s, it.f)));
            }
        }
    }

    fout<<tot<<'\n';
    fout<<nrm<<'\n';
    for (i=2; i<=n; i++)
    {
        fout<<p[i]<<" "<<i<<'\n';
    }

    fin.close();
    fout.close();
    return 0;
}