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

using namespace std;

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

const int MAX=1e5+5;
const int INF=1e9;
int n,m,a,b,c,cost,t[MAX],viz[MAX],key[MAX];
struct T
{
    int nod,cost;
};
vector < T > v[MAX];
struct cmp
{
    bool operator()(T a, T b)
    {
        return a.cost>b.cost;
    }
};
priority_queue < T , vector < T > , cmp > pq;

int main()
{
    fin >> n >> m;
    for(int i=1;i<=m;i++)
    {
        fin >> a >> b >> c;
        v[a].push_back({b,c});
        v[b].push_back({a,c});
    }
    for(int i=2;i<=n;i++)
        key[i]=INF; // costul muchiei prin care s-a ajuns la i
    pq.push({1,0});
    while(!pq.empty())
    {
        int nod=pq.top().nod;
        pq.pop();
        viz[nod]=1;
        for(auto vec : v[nod])
            if(!viz[vec.nod] && vec.cost<key[vec.nod])
            {
                t[vec.nod]=nod;
                key[vec.nod]=vec.cost;
                pq.push(vec);
            }
    }
    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;
}