#include <bits/stdc++.h>

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

int n,m;
int tata[400005];
int x,y,cost;
int ans;
vector <int> lst[200005];
vector <pair<int,int> > ras;
struct date
{
    int x,y,cost;
} muchii[400005],alfa;
bool sortbycomp(date a,date b)
{
    return (a.cost<b.cost);
}
void unire(int x,int y)
{
    x=tata[x];
    y=tata[y];
    if(x!=y)
    {
    if(lst[x].size()<lst[y].size())
        swap(x,y);
    while(!lst[y].empty())
    {
        int nod=lst[y].back();
        lst[x].push_back(nod);
        lst[y].pop_back();
        tata[nod]=x;
    }
    }
}
int main()
{
    ios_base::sync_with_stdio(0);
    fin.tie(0);
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        fin>>alfa.x>>alfa.y>>alfa.cost;
        muchii[i]=alfa;
    }
    for(int i=1;i<=n;i++)
        {
            lst[i].push_back(i);
            tata[i]=i;
        }
    sort(muchii+1,muchii+m+1,sortbycomp);
    for(int i=1;i<=m;i++)
    if(tata[muchii[i].x]!=tata[muchii[i].y])
        {
            int a=muchii[i].x;
            int b=muchii[i].y;
            unire(a,b);
            ras.push_back(make_pair(a,b));
            ans+=muchii[i].cost;
            if(ras.size()==n-1)
                break;
        }
    fout<<ans<<'\n';
    fout<<ras.size()<<'\n';
    for(int i=0;i<ras.size();i++)
    fout<<ras[i].first<<' '<<ras[i].second<<'\n';
    return 0;
}