#include <fstream>
#define INF 10000
using namespace std;

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

int n, start, costmin;
int cmin[1501], c[1501][1501];
int viz[1501], tata[1501];

void citire();
void prim();
void afisare();

int main()
{
    citire();
    prim();
    afisare();
    return 0;
}

void citire()
{
    int i, m, x, y, cost, j;
    fin>>n>>m; start=1;
    for(i=1;i<=n;i++)
    {
        for(j=1;j<=n;j++)
                c[i][j]=INF;
        c[i][i]=0;
    }
    for(i=1;i<=m;i++)
    {
        fin>>x>>y>>cost;
        c[x][y]=c[y][x]=cost;
    }
    for(i=1;i<=n;i++)
    {
        cmin[i]=c[start][i];
        tata[i]=start;
    }
    tata[start]=0; viz[start]=1; cmin[start]=0;
}

void prim()
{
    int vfmin, i, x, nrmin, neviz=n-1;
    while(neviz)
    {
        nrmin=INF;
        for(i=1;i<=n;i++)
            if(!viz[i]&&nrmin>cmin[i])
            {
                nrmin=cmin[i]; vfmin=i;
            }
            viz[vfmin]=1; neviz--;
            //fout<<vfmin<<' '<<tata[vfmin]<<'\n';
            costmin+=c[vfmin][tata[vfmin]];
            for(x=1;x<=n;x++)
                if(c[vfmin][x]<INF)
                    if(!viz[x]&&cmin[x]>c[x][vfmin])
                    {
                        cmin[x]=c[vfmin][x];
                        tata[x]=vfmin;
                    }
    }
}

void afisare()
{
    int i;
    fout<<costmin<<'\n'<<n-1<<'\n';
    for(i=n;i>1;i--)
        fout<<tata[i]<<' '<<i<<'\n';
}