#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#define Nmax 200000
#define INF 1e9

using namespace std;

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

vector<pair<int,int>> g[Nmax + 5];
int TT[Nmax + 5], d[Nmax + 5];
bool viz[Nmax + 5];

int n,m,x,y,c,sum;

void prim(int Node)
{
    priority_queue<pair<int,int>,vector<pair<int,int>>,greater<pair<int,int>>> pq;
    pq.push(make_pair(0,Node));
    while(!pq.empty())
    {
        int nod = pq.top().second;
        pq.pop();
        if(!viz[nod])
        {
            for(auto i : g[nod])
            {
                if(d[i.second] > i.first && !viz[i.second])
                {
                    d[i.second]=i.first;
                    TT[i.second]=nod;
                    pq.push(make_pair(i.first,i.second));
                }
            }
        }
        viz[nod]=true;
    }
}

int main()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        fin>>x>>y>>c;
        g[x].push_back(make_pair(c,y));
        g[y].push_back(make_pair(c,x));
    }
    for(int i=2; i<=n; i++)
    {
        d[i]=INF;
    }
    d[1]=0;
    prim(1);
    for(int i=2; i<=n; i++)
        sum += d[i];
    fout << sum << '\n';
    fout << n-1 << '\n';
    for(int i=2; i<=n; i++)
    {
        fout << i << " " << TT[i] << '\n';
    }
    return 0;
}