#include <bits/stdc++.h>
#define dm 400002

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

struct nod{
    int x;
    int y;
    int cost;
};

int n, m, i, p[dm/2], s;
vector <nod> vv;
nod v[dm];

int cmp(nod a, nod b)
{
    return a.cost<b.cost;
}

int parinte(int x)
{
    if(p[x]==x)
        return p[x];
    else
        return p[x]=parinte(p[x]);
}

void ad(int x, int y)
{
    p[parinte(x)]=p[parinte(y)];
}

int main()
{
    f>>n>>m;
    for(i=1; i<=m; i++)
    {
        f>>v[i].x>>v[i].y>>v[i].cost;

    }
    sort(v+1, v+m+1, cmp);
//    for(i=1; i<=m; i++)
//    {
//        cout<<v[i].x<<' '<<v[i].y<<' '<<v[i].cost<<'\n';
//    }
    for(i=1; i<=n; i++)
        p[i]=i;
    ///vv.push_back({v[1].x, v[1].y, v[1].cost});
    for(i=1; i<=m; i++)
    {
        if(parinte(v[i].y)!=parinte(v[i].x))
        {
            vv.push_back({v[i].x, v[i].y, v[i].cost});
            p[parinte(v[i].x)]=parinte(v[i].y);
            s+=v[i].cost;
        }
    }
    g<<s<<'\n';
    g<<n-1<<'\n';
    for(i=0; i<vv.size(); i++)
    {
        g<<vv[i].x<<' '<<vv[i].y<<'\n';
    }

    return 0;
}