#include<bits/stdc++.h>
#define maxn 400005
using namespace std;

ifstream fin("apm.in");
ofstream fout("apm.out");

pair<int,int> p[maxn];

int n,m,total,tt[maxn],k,rg[maxn];

struct Edge
{
    int x,y,c;
}V[maxn];

bool compara(Edge a,Edge b)
{
    return a.c<b.c;
}

void citire()
{
    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,compara);

    /*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++)
    {
        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()
{
    citire();
    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;
}