/// prim
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

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

const int max_size = 2e5 + 1, INF = 1e9 + 1;

struct str{
    int x, cost;
    bool operator < (const str & aux) const
    {
        return cost > aux.cost;
    }
};

int d[max_size], uz[max_size], rez, n, t[max_size];
vector <pair <int, int>> mc[max_size], ans;
priority_queue <str> pq;

void djk ()
{
    for (int i = 1; i <= n; i++)
    {
        d[i] = INF;
    }
    d[1] = 0;
    pq.push({1, 0});
    while (!pq.empty())
    {
        int nod = pq.top().x, val = pq.top().cost;
        pq.pop();
        if (uz[nod])
        {
            continue;
        }
        uz[nod] = 1;
        rez += val;
        if (nod != 1)
        {
            ans.push_back({t[nod], nod});
        }
        for (auto f : mc[nod])
        {
            if (f.second < d[f.first] && !uz[f.first])
            {
                t[f.first] = nod;
                pq.push({f.first, f.second});
            }
        }
    }
}

int main ()
{
    int m;
    in >> n >> m;
    while (m--)
    {
        int x, y, c;
        in >> x >> y >> c;
        mc[x].push_back({y, c});
        mc[y].push_back({x, c});
    }
    djk();
    out << rez << '\n' << ans.size() << '\n';
    for (auto f : ans)
    {
        out << f.first << " " << f.second << '\n';
    }
    in.close();
    out.close();
    return 0;
}