#include <iostream>
#include <fstream>
#include <algorithm>

using namespace std;

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

const int MMax = 400005;

pair < int, int > P[MMax];
int k;

int N,M,Total,TT[MMax], RG[MMax];

struct Muchie{
    int x,y,cost;
}V[MMax];

bool Compare(Muchie a,Muchie b){
    return a.cost < b.cost;
}

void Read(){
    f >> N >> M;

    for(int i = 1; i <= M;i++)
        f >> V[i].x >> V[i].y >> V[i].cost;

    sort(V + 1, V + M + 1, Compare);

    for(int i = 1; i <= N;i++){
        TT[i] = i;
        RG[i] = 1;
    }
}

void Unire(int x, int y){
    if(RG[x] < RG[y])
        TT[x] = y;
    if(RG[x] > RG[y])
        TT[y] = x;
    if(RG[x] == RG[y]){
        TT[x] = y;
        RG[y]++;
    }
}

int Find(int Nod){
      while(TT[Nod] != Nod)
            Nod = TT[Nod];
      return Nod;
}

void Solve(){
    for(int i = 1 ;i <= M;i++){
        int TataX = Find(V[i].x);
        int TataY = Find(V[i].y);
        if(TataX != TataY){
            Unire(TataX,TataY);
            P[++k].first = V[i].x;
            P[k].second = V[i].y;
            Total+=V[i].cost;
        }
    }
}

void Afisare(){
    g << Total << "\n";
    g << k <<"\n";

    for(int i = 1; i <= k;i++)
        g << P[i].first << " " << P[i].second << "\n";
}
int main()
{
    Read();
    Solve();
    Afisare();
    return 0;
}