#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("apm.in");
ofstream fout("apm.out");
struct muc
{
  int x,y,c;
}v[200001];
int i,j,n,m,cost,viz[200001],s,nr,rez[2][200001],w;

int cmp(const muc a,const muc b)
{
    return a.c<b.c;
}
int main()
{
    fin>>n>>m;
    for(i=1;i<=m;++i)
        fin>>v[i].x>>v[i].y>>v[i].c;
    sort(v+1,v+m+1,cmp);

    for(i=1;i<=m;++i)

        if(viz[v[i].y]==0||viz[v[i].x]==0)
            {
                nr++;
                s+=v[i].c;
                viz[v[i].y]=1;
                w++;
                rez[0][w]=v[i].x;
                rez[1][w]=v[i].y;
                viz[v[i].x]=1;
            }
    fout<<s<<'\n';
    fout<<w<<'\n';
    for(i=1;i<=w;++i)
        fout<<rez[0][i]<<" "<<rez[1][i]<<'\n';

    return 0;
}