#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin ("apm.in");
ofstream fout ("apm.out");
pair <int,int> p[400005];
int n,m,tt[400005],rg[400005],k,cost;
struct muchie{int x,y,c;}v[400005];
bool comp(muchie a,muchie b)
{
    return a.c<b.c;
}
int tata(int nod)
{
    while(tt[nod]!=nod)
        nod=tt[nod];
    return nod;
}
int main()
{
    fin>>n>>m;
    for(int i=1;i<=m;i++)
        fin>>v[i].x>>v[i].y>>v[i].c;

    sort(v+1,v+m+1,comp);
    for(int i=1;i<=n;i++)
    {
        tt[i]=i;
        rg[i]=1;
    }
    for(int i=1;i<=m;i++)
    {
        int x=tata(v[i].x);
        int y=tata(v[i].y);
        if(x!=y)
        {
            cost+=v[i].c;
            if(rg[x]<rg[y])
                tt[x]=y;
            if(rg[y]<rg[x])
                tt[y]=x;
            if(rg[x]==rg[y])
            {
                tt[x]=y;
                rg[y]++;
            }
            p[++k].first=v[i].x;
            p[k].second=v[i].y;
        }
    }
    fout<<cost<<'\n';
    fout<<n-1<<'\n';
    for(int i=1;i<=k;i++)
    {
        fout<<p[i].first<<" "<<p[i].second<<'\n';
    }
    return 0;
}