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

//kruskal
const int NMAX=400000;
struct muchie{
    int x,y,c;
};
muchie a[NMAX+1];
int h[NMAX+1],d[NMAX+1]; //h - rang,d - tata

bool cmp(muchie &p,muchie &q)
{
    return p.c<q.c;
}

void Union(int x,int y)
{
    if(h[x]>h[y]) d[y]=x;
    else
    {
        d[x]=y;
        if(h[x]==h[y]) h[y]++;
    }
}

int Find(int x)
{
    int r, y, t;
    r=x;
    while(d[r] != r) {
        r=d[r];
    }
    y=x;
    while(y!=r)
    {
        t=d[y];
        d[y]=r;
        y=t;
    }
    return r;
}

int main()
{
    int n,m,s=0; vector<muchie> sol;
    ifstream f("apm.in");
    ofstream g("apm.out");
    f>>n>>m;
    for(int i=1;i<=n;i++)
    {
        h[i]=1; d[i]=i;
    }
    for(int i=1;i<=m;i++)
        f>>a[i].x>>a[i].y>>a[i].c;
    sort(a+1,a+m+1,cmp);
    for(int i=1;i<=m;i++)
    {
        int p=Find(a[i].x);
        int q=Find(a[i].y);
        if(p!=q)
        {
            s=s+a[i].c;
            sol.push_back(a[i]);
            Union(p,q);
        }
    }
    g<<s<<endl;
    g<<n-1<<endl;
    for(int i=0;i<n-1;i++)
        g<<sol[i].y<<" "<<sol[i].x<<endl;
    return 0;
}