#include <fstream>
#include <vector>
#define INF 2000000000
#define DIMN 200010
#define DIMM 400010
using namespace std;
int n,m,i,j,k,x,y,cost,minim,s,el;
vector < pair<int,int> > L[DIMM];
int d[DIMN],f[DIMN],t[DIMN];
pair <int,int> sol[DIMN];
int main (){

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

    fin>>n>>m;
    for (i=1;i<=m;i++){
        fin>>x>>y>>cost;
        L[x].push_back (make_pair(y,cost));
        L[y].push_back (make_pair(x,cost));
    }
    d[1] = 0;
    for (i=2;i<=n;i++)
        d[i] = INF;
    for (i=1;i<=n;i++){
        minim = INF;
        for (j=1;j<=n;j++)
            if (f[j] == 0 && d[j] < minim){
                minim = d[j];
                k = j;
            }
        if (i != 1){
            sol[++el].first = k;
            sol[el].second = t[k];
            s += d[k];
        }
        f[k] = 1;
        for (j=0;j<L[k].size();j++){
            int vecin = L[k][j].first;
            int cst = L[k][j].second;
            if (f[vecin] == 0 && d[vecin] > cst){
                d[vecin] = cst;
                t[vecin] = k;
            }
        }
    }
    fout<<s<<"\n"<<n-1<<"\n";
    for (i=1;i<n;i++)
        fout<<sol[i].first<<" "<<sol[i].second<<"\n";

    return 0;
}