#include <iostream>
#include <cstdio>
#include <queue>
#include <vector>
#define NMAX 200005
#define MAX 0x3f3f3f

using namespace std;

int n, m, viz[NMAX], dist[NMAX], tata[NMAX];

priority_queue <pair <int, int> > Q;
vector <pair <int, int> > g[NMAX];
vector <pair <int, int> >::iterator it;

void read()
{
    scanf("%d%d", &n, &m);
    for(int i=1; i<=m; ++i)
    {
        int x, y, c;
        scanf("%d%d%d", &x, &y, &c);
        g[x].push_back(make_pair(y, c));
        g[y].push_back(make_pair(x, c));
    }
    dist[1] = 0;
    tata[1] = 1;
    viz[1] = 1;
    for(int i=2; i<=n; ++i)
    {
        tata[i] = i;
        dist[i] = MAX;
    }
}

void solvePrimAlgorithm()
{
    Q.push(make_pair(0, 1));
    while(!Q.empty())
    {
        int cost = -1 * Q.top().first;
        int nodCurent = Q.top().second;
        Q.pop();
        viz[nodCurent] = 1;
        for(it = g[nodCurent].begin(); it != g[nodCurent].end(); ++it)
            if(viz[it->first]==0 && dist[it->first] > it->second)
            {
                dist[it->first] = it->second;
                tata[it->first] = nodCurent;
                Q.push(make_pair(-1*it->second, it->first));
            }
    }
}

void afisare()
{
    int distTotatla = 0;
    for(int i=2; i<=n; ++i)
        distTotatla += dist[i];
    printf("%d\n", distTotatla);
    printf("%d\n", n-1);
    for(int i=2; i<=n; ++i)
        printf("%d %d\n", tata[i], i);
}

int main()
{
    freopen("apm.in", "r", stdin);
    freopen("apm.out", "w", stdout);
    read();
    solvePrimAlgorithm();
    afisare();
    return 0;
}