#include <fstream>
#include <algorithm>
using namespace std;

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

struct inf{
    int x, y, c;
}v[400005];

int n, m;
int t[400005], rang[400005];
long long sum;
pair <int, int> z[400005];

bool cmp(inf a, inf b)
{
    return a.c <= b.c;
}

int rad(int nod)
{
    if(t[nod]==0)
        return nod;
    else
    {
        int aux=rad(t[nod]);
        t[nod]=aux;
        return aux;
    }
}

void unire(int a, int b)
{
    int ra=rad(a), rb=rad(b);
    if(ra!=rb)
    {
        if(rang[ra] > rang[rb])
            t[rb]=ra;
        else{
            t[ra]=rb;
            if(rang[ra]==rang[rb])
                rang[rb]++;
        }
    }
}

int main()
{
    f>>n>>m;
    for(int i=1; i<=m; i++)
    {
        f>>v[i].x;
        f>>v[i].y;
        f>>v[i].c;
    }
    sort(v+1, v+m+1, cmp);
    int i=0, j=0;
    while(n>1)
    {
        int a=v[i].x;
        int b=v[i].y;
        int cost=v[i].c;
        if(rad(a)!=rad(b))
        {
            unire(a, b);
            z[++j]=make_pair(a, b);
            n--;
            sum+=cost;
        }
        i++;
    }
    g<<sum<<'\n';
    g<<j<<'\n';
    for(i=1; i<=j; i++)
        g<<z[i].first<<" "<<z[i].second<<'\n';
    return 0;
}