#include <iostream>
#include <fstream>
#include <algorithm>
#define N 105
using namespace std;


ifstream fin ("apm.in");
ofstream fout ("apm.out");
int n,m;
int a[N][N];
int *l[N];
int lg[N];

bool vizit[N];
int que[N];
int prim,ultim;
int height[N];

int parinte[1005];
bool viz[101];

struct Muchie
{
    int i,j;
    int cost;
}muchie[1005];


int nrSelec=0;
int costTotal=0;
Muchie apcm[105];
void readGraph()
{
    fin>>n>>m;
    for(int i=1;i<=m;++i)
    {
        fin>>muchie[i].i>>muchie[i].j>>muchie[i].cost;
    }
}


int Find(int v)
{
    if(parinte[v]==0)
        return v;
    else
    {
        parinte[v]=Find(parinte[v]);   
        return parinte[v];
    }
}

void Union(int u, int v)
{
    int reprez_u=Find(u);
    int reprez_v=Find(v);

    if(height[reprez_u]>height[reprez_v])
    {
        parinte[reprez_v]=reprez_u;
    }
    else
    {
        parinte[reprez_u]=reprez_v;
        if(height[reprez_u]==height[reprez_v])
			height[reprez_v]=height[reprez_v]+1;
    }
}
bool comp(Muchie a, Muchie b)
{
    if (a.cost < b.cost)
        return 1;
    else
        return 0;
}

void Krukal()
{
    for(int i=1;i<=n;++i)
    {
        parinte[i]=0;
        height[i]=0;
    }
    sort(muchie+1, muchie+m+1, comp);

    for(int i=1;i<=m;++i)
    {
        if(Find(muchie[i].i)!=Find(muchie[i].j))
        {
            nrSelec++;
            costTotal+=muchie[i].cost;
            apcm[nrSelec]=muchie[i];
            Union(muchie[i].i,muchie[i].j);
            if(nrSelec==n-1)
	            break;
        }
    }
}

void kruskal2()
{
    ///faci union(daca nu sunt ciclu) deja la ele si apoi kruskal normal
}

void Primm()
{

}

int main()
{
    readGraph();
    Krukal();
    fout<<nrSelec<<"\n";
    fout<<costTotal<<"\n";
    for(int i=1;i<=nrSelec;++i)
    {
        fout<<apcm[i].i<<" "<<apcm[i].j<<"\n";
    }
    return 0;

}