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

const int nm=2e5+5;

int parent[nm], sz[nm];
pair<int, int> rez[nm];

struct Cows
{
    int n1, n2, cost;
}v[2*nm];

int fin(int a)
{
    if(a==parent[a])
        return a;
    return parent[a]=fin(parent[a]);
}

void unite(int a, int b)
{
    a=fin(a);
    b=fin(b);
    if(sz[a]<sz[b])
        swap(a, b);
    parent[b]=a;
    sz[a]+=sz[b];
    sz[b]=0;
}

bool cmp(Cows a, Cows b)
{
    return a.cost<b.cost;
}

int main()
{
    ifstream cin("apm.in");
    ofstream cout("apm.out");
    int n, m, sum=0, pz=0;
    cin>>n>>m;
    for(int i=1; i<=n; i++)
    {
        parent[i]=i;
        sz[i]=1;
    }
    for(int i=1; i<=m; i++)
        cin>>v[i].n1>>v[i].n2>>v[i].cost;
    sort(v+1, v+m+1, cmp);
    for(int i=1; i<=m; i++)
    {
        if(fin(v[i].n1)!=fin(v[i].n2))
        {
            rez[++pz]={v[i].n1, v[i].n2};
            sum+=v[i].cost;
            unite(v[i].n1, v[i].n2);
        }
    }
    cout<<sum<<'\n';
    cout<<pz<<'\n';
    for(int i=1; i<=pz; i++)
        cout<<rez[i].first<<" "<<rez[i].second<<'\n';
    return 0;
}