#include <fstream>
#include <algorithm>
#define cost first
#define st second.first
#define dr second.second
using namespace std;
ifstream f("apm.in");
ofstream g("apm.out");
int n, m, rx, ry, t[400001], s, k, p[400001], u[400001];
pair<int, pair<int, int> > l[400010];
int rad (int x){
    while(t[x]>0)
        x=t[x];
    return x;
}
int main(){
    f>>n>>m;
    for(int i=1;i<=n;i++)
        t[i]=-1;
    for(int i=1;i<=m;i++)
        f>>l[i].st>>l[i].dr>>l[i].cost;
    sort(l+1,l+m+1);
    for(int i=1;i<=m;i++)
    {
        rx=rad(l[i].st);
        ry=rad(l[i].dr);
        if(rx!=ry)
        {
            s+=l[i].cost;
            p[++k]=l[i].st;
            u[k]=l[i].dr;
            if(t[rx]<t[ry])
            {
                t[rx]+=t[ry];
                t[ry]=rx;
            }
            else
            {
                t[ry]+=t[rx];
                t[rx]=ry;
            }
        }
    }
    g<<s<<"\n"<<k<<"\n";
    for(int i=1;i<=k;i++)
        g<<p[i]<<" "<<u[i]<<"\n";
}