#include <fstream>
#include <vector>

#define inf 2e9
#define maxn 2 * 100010

using namespace std;

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

int n, m, d[maxn], t[maxn], tcost;
vector <pair <int, int> > g[maxn];
bool u[maxn];

void algPrim()
{
    int nmin, node;
    vector <pair <int, int> > :: iterator it;
    for (int i = 2; i <= n; i++)
        d[i] = inf;
    for (int k = 1; k <= n; k++)
    {
        nmin = inf;
        for (int i = 1; i <= n; i++)
        {
            if (!u[i] && d[i] < nmin)
            {
                nmin = d[i];
                node = i;
            }
        }
        tcost += nmin;
        u[node] = 1;
        for (it = g[node].begin(); it != g[node].end(); ++it)
        {
            int v = it -> first;
            int c = it -> second;
            if (!u[v] && d[v] > c)
            {
                d[v] = c;
                t[v] = node;
            }
        }
    }
    fout << tcost << '\n';
    fout << n - 1 << '\n';
    for (int i = 2; i <= n; i++)
        fout << i << " " << t[i] << '\n';
}

int main()
{
    fin >> n >> m;
    for (int a, b, c; m; --m)
    {
        fin >> a >> b >> c;
        g[a].push_back(make_pair(b, c));
        g[b].push_back(make_pair(a, c));
    }
    algPrim();
    return 0;
}