#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
const int nmax=400005;
pair <int,int> rez[nmax];
int n,m,cnt,sum,tt[nmax/2],rg[nmax/2];
struct muchie
{
    int x,y,cost;
}v[nmax];
bool cmp(muchie a,muchie b)
{
    return a.cost<b.cost;
}
int findset(int nod)
{
    while (tt[nod]!=nod)
        nod=tt[nod];
    return nod;
}
void unionset(int x,int y)
{
    if (rg[x]==rg[y])
    {
        tt[y]=x;
        rg[x]++;
    }
    else if (rg[x]>rg[y]) tt[y]=x;
    else tt[x]=y;
}
int main()
{
    fin >> n >> m;
    for (int i=1;i<=m;i++)
    {
        fin >> v[i].x >> v[i].y >> v[i].cost;
    }
    sort (v+1,v+m+1,cmp);
    for (int i=1;i<=n;i++)
    {
        tt[i]=i;
        rg[i]=1;
    }
    for (int i=1;i<=m;i++)
    {
        int ttx=findset(v[i].x);
        int tty=findset(v[i].y);
        if (ttx!=tty)
        {
            unionset(ttx,tty);
            cnt++;
            rez[cnt].first=v[i].x;
            rez[cnt].second=v[i].y;
            sum+=v[i].cost;
        }
    }
    fout << sum << '\n';
    fout << cnt << '\n';
    for (int i=1;i<=cnt;i++)
    {
        fout << rez[i].first << " " << rez[i].second << '\n';
    }
}