#include<bits/stdc++.h>
#define N 400001
using namespace std;
ifstream in("apm.in");
ofstream out("apm.out");

int n, m, ans, ind[N], GR[N];
struct edge{int x,y,c;}a[N];
vector<int> v;

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

void unity(int i,int j)
{
    GR[group(i)]=group(j);
}

struct cmp{
    bool operator()(edge x, edge y)
    {
        return x.c<y.c;
    }
};

int main()
{
    in>>n>>m;
    for(int i=0;i<m;++i)
    {
        in>>a[i].x>>a[i].y>>a[i].c;
        ind[i] = i;
    }
    for(int i=1;i<=N;++i)
        GR[i]=i;
    sort(a+1, a+m+1, cmp());
    for(int i=0;i<m;++i)
    {
        if(group(a[ind[i]].x) != group(a[ind[i]].y))
        {
            ans+=a[ind[i]].c;
            unity(a[ind[i]].x,a[ind[i]].y);
            v.push_back(ind[i]);
        }
    }
    out<<ans<<'\n';
    out<<n-1<<'\n';
    for(int i=0;i<n-1;++i)
        out<<a[v[i]].x<<' '<<a[v[i]].y<<'\n';
    return 0;
}