#include <bits/stdc++.h>
#define Nmax 200005
#define Mmax 400005

using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");


struct structura{
    int first,second,third;
};
int n,m,T[Nmax],R[Nmax],sum;
vector<structura>M;
vector<pair<int,int> > sol;

int root(int k)
{
    if(T[k]==k)
        return k;
    else return T[k] = root(T[k]);
}

void Union(int a,int b)
{
    if(R[a] > R[b])
        T[b] = a;
    else
    {
        T[a] = b;
        if(R[a] == R[b])
            R[b]++;
    }


}

bool Compare(structura a, structura b)
{
    return a.third < b.third;
}

int main()
{
    f>>n>>m;
    for(int i = 1; i <= m; i++)
    {
        int x,y,c;
        f>>x>>y>>c;
        M.push_back({x,y,c});
    }
    for(int i = 1; i <= n; i++)
    T[i]=i,R[i]=1;

    sort(M.begin(),M.end(),Compare);
    for(vector<structura>::iterator it = M.begin(); it < M.end(); it++)
    {
        int x = root(it->first);
        int y = root(it->second);
        if(T[x]!=T[y])
        {
            Union(x,y);
            sol.push_back({it->first,it->second});
            sum+=it->third;


        }

    }
    g<<sum<<"\n";
    g<<sol.size()<<"\n";
    for(vector<pair<int,int > >::iterator it = sol.begin(); it < sol.end(); it++)
        g<<it->first<<" "<<it->second<<"\n";



    return 0;
}