#include<bits/stdc++.h>

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

int GR[400100];
int n,m,ANS,IND[400100];
vector<int> sol;

struct bum
{
    int x,y,c;
} a[400100];

int grupa(int i)
{
    if(GR[i] == i) return i;
    GR[i] = grupa(GR[i]);
    return GR[i];
}

void reuniune(int i,int j)
{
    GR[grupa(i)] = grupa(j);
}

bool compare(int i,int j)
{
    return(a[i].c < a[j].c);
}

int main()
{
    f>>n>>m;
    for(int i=1; i<=m; ++i)
    {
        f>>a[i].x>>a[i].y>>a[i].c;
        IND[i] = i;
    }
    for(int i=1; i<=n; ++i) GR[i] = i;
    sort(IND+1,IND+m+1,compare);
    for(int i=1; i<=m; ++i)
    {
        if(grupa(a[IND[i]].x)!=grupa(a[IND[i]].y))
        {
            ANS+=a[IND[i]].c;
            reuniune(a[IND[i]].x,a[IND[i]].y);
            sol.push_back(IND[i]);
        }
    }
    g<<ANS<<'\n'<<n-1<<'\n';
    for(int i=0; i<n-1; ++i)
        g<<a[sol[i]].x<<' '<<a[sol[i]].y<<'\n';
    return 0;
}