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

using namespace std;

int n, m, viz[NMAX], tata[NMAX], distanta[NMAX];
vector <pair <int, int> > g[NMAX];
vector <pair <int, int> >::iterator it;
priority_queue <pair <int, int> > q;

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

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

void afisare()
{
    int raspunsDistanta=0;
    for(int i=1; i<=n; ++i)
        raspunsDistanta+=distanta[i];
    printf("%d\n%d\n", raspunsDistanta, 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();
    apm();
    afisare();
    return 0;
}