#include <fstream>
#include <iostream>
#include <algorithm>
using namespace std;
ifstream f("apm.in");
ofstream g("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()
{
    f>> N >> M;
    for(int i = 1; i <= M; i++)
        f>> V[i].x >> V[i].y >> V[i].c;
    sort(V+1, V+M+1, Compare);
}
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++)
    {
        if(Find(V[i].x) != Find(V[i].y))
        {
            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();
    g<< Total << "\n";
    g<< N-1 <<"\n";
    for(int i = 1; i <= k; i++)
        g<< P[i].first << " " << P[i].second << "\n";
    return 0;
}