#include <bits/stdc++.h>

using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
int viz[200005],val[200005],poz,n,m,x,y,cost,sol,i,tata[200005];
vector <pair <int,int > > v[200005],solutie;
void dfs (int x)
{
    int i,nod,cost,minim;
    viz[x]=1;
    for (i=0;i<v[x].size();i++)
    {
        nod=v[x][i].first;
        cost=v[x][i].second;
        if (val[nod]>cost)
        {
            val[nod]=cost;
            tata[nod]=x;
        }
    }
    poz=0;
    minim=INT_MAX;
    for (i=1;i<=n;i++)
    {
        if (viz[i]==0&&val[i]<minim)
        {
            minim=val[i];
            poz=i;
        }
    }
    if (poz!=0)
    {
        sol+=minim;
        solutie.push_back({poz,tata[poz]});
        dfs(poz);
    }
}
int main()
{
    f>>n>>m;
    for (i=1;i<=m;i++)
    {
        f>>x>>y>>cost;
        v[x].push_back({y,cost});
        v[y].push_back({x,cost});
    }
    for (i=1;i<=n;i++)
    {
        val[i]=INT_MAX;
    }
    val[1]=0;
    dfs(1);
    g<<sol<<'\n';
    g<<solutie.size()<<'\n';
    for (i=0;i<solutie.size();i++)
    {
        g<<solutie[i].first<<" "<<solutie[i].second<<'\n';
    }
    return 0;
}