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#include    <fstream>
#include    <iostream>
#include    <algorithm>
 
using namespace std;
 
ifstream    fin("apm.in");
ofstream    fout("apm.out");
 
const int NMax = 400005;
 
pair <int,int> P[NMax];
 
int N, M, Total, TT[NMax], k, RG[NMax];
 
struct Edge
{
    int x,y,c;
 
}V[NMax];
 
bool Compare(Edge a, Edge b)
{
    return a.c < b.c;
}
 
void Read()
{
    fin >> N >> M;
 
    for(int i = 1; i <= M; i++)
        fin >> V[i].x >> V[i].y >> V[i].c;
 
    sort(V+1, V+M+1, Compare);
 
    for(int i = 1; i <= M; i++)
        cout << V[i].x << " " << V[i].y << " " << V[i].c << "\n";
}
 
int Find(int nod)
{
    while(TT[nod] != nod)
        nod = TT[nod];
    return nod;
}
 
void Unite(int x, int y)
{
    if(RG[x] < RG[y])
        TT[x] = y;
    if(RG[y] < RG[x])
        TT[y] = x;
    if(RG[x] == RG[y])
    {
        TT[x]=y;
        RG[y]++;
    }
}
 
void Solve()
{
    for(int i=1;i<=M;i++)
    {
        //cout << "Incerc " << V[i].x << " cu " << V[i].y << "\n";
        if(Find(V[i].x) != Find(V[i].y))
        {
            //cout << "Unesc " << V[i].x << " cu " << V[i].y << "\n\n";
            Unite(Find(V[i].x), Find(V[i].y));
            P[++k].first    =   V[i].x;
            P[k].second     =   V[i].y;
            Total           +=  V[i].c;
        }
    }
}
 
int main()
{
    Read();
 
    for(int i = 1; i <= M; i++)
    {
        TT[i]=i;
        RG[i]=1;
    }
 
    Solve();
 
    fout << Total << "\n";
    fout << N-1 <<"\n";
 
    for(int i = 1; i <= k; i++)
        fout << P[i].first << " " << P[i].second << "\n";
 
    return 0;
}