#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

const int MAX=2*(1e5)+5;
const int INF=1e9+5;
typedef pair < int, int > ip;
int n,m,a,b,c,cost,t[MAX],key[MAX],viz[MAX];
vector < ip > v[MAX];
priority_queue < ip, vector < ip >, greater < ip > > pq;

int main()
{
    fin >> n >> m;
    while(m--)
    {
        fin >> a >> b >> c;
        v[a].push_back(make_pair(b,c));
        v[b].push_back(make_pair(a,c));
    }
    for(int i=2;i<=n;i++)
        key[i]=INF;
    pq.push(make_pair(0,1));
    while(!pq.empty())
    {
        int u=pq.top().second;
        pq.pop();
        viz[u]=1;
        for(auto vec : v[u])
        {
            int nod=vec.first;
            int cst=vec.second;
            if(!viz[nod] && cst<key[nod])
            {
                t[nod]=u;
                key[nod]=cst;
                pq.push(make_pair(cst,nod));
            }
        }
    }
    for(int i=1;i<=n;i++)
        cost+=key[i];
    fout << cost << '\n' << n-1 << '\n';
    for(int i=2;i<=n;i++)
        fout << t[i] << " " << i << '\n';
	return 0;
}