#include <algorithm>
#include <fstream>
#include <vector>

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

const int Nmax = 200005;
int n, m, Suma, t[Nmax], r[Nmax];
vector <pair <int, int> > Sol;
struct mango
{
    int x, y, cost;
} G[Nmax];

bool Crit(mango a, mango b)
{
    return a.cost < b.cost;
}

void Read()
{
    f>>n>>m;
    for(int i = 1; i <= m; i++) f>>G[i].x>>G[i].y>>G[i].cost;
    sort(G+1, G+m+1, Crit);
    for(int i = 1; i <= n; i++) t[i] = i;
}

int Tata(int k)
{
    while(k != t[k]) k = t[k];
    return k;
}

void Unite(int a, int b)
{
    if(r[a] == r[b]) t[a] = b, r[b]++;
    if(r[a] < r[b]) t[a] = b;
    if(r[a] > r[b]) t[b] = a;
}

void Solve()
{
    for(int i = 1; i <= m; i++)
    {
        if(Tata(G[i].x) != Tata(G[i].y))
        {
            Suma += G[i].cost;
            Unite(Tata(G[i].x),Tata(G[i].y));
            Sol.push_back(make_pair(G[i].x, G[i].y));
        }
    }
}

void Print()
{
    g<<Suma<<'\n';
    g<<Sol.size()<<'\n';
    for(int i = 0; i < (int)Sol.size(); i++) g<<Sol[i].first<<' '<<Sol[i].second<<'\n';
}

int main()
{
    Read();
    Solve();
    Print();
    return 0;
}