#include <cstdio>
#include <algorithm>
#include <vector>
#define INF 2000000000
#define MAXN 200001
using namespace std;
int d[MAXN],heap[MAXN],poz[MAXN],s[MAXN],ans,k;
vector <pair <int,int> >v[MAXN],sol;
inline void down(int p)
{
    int minim,x;
    bool ok=true;
    while((x=p<<1)<=k && ok)
    {
        ok=false;
        if(x<k && d[heap[x+1]]<d[heap[x]])
            minim=x+1;
        else
            minim=x;
        if(d[heap[minim]]<d[heap[p]])
        {
            swap(poz[heap[minim]],poz[heap[p]]);
            swap(heap[minim],heap[p]);
            p=minim;ok=true;
        }
    }
}
inline void pop()
{
    swap(poz[heap[1]],poz[heap[k]]);
    swap(heap[1],heap[k]);
    k--;down(1);
}
inline void up(int p)
{
    int x;
    while((x=p>>1) && d[heap[x]]>d[heap[p]])
    {
        swap(poz[heap[x]],poz[heap[p]]);
        swap(heap[x],heap[p]);
        p=x;
    }
}
inline void push(int x)
{
    heap[++k]=x;poz[x]=k;
    up(k);
}
inline void adauga_in_apm(int x)
{
    int y,cost;
    ans+=d[x];
    for(unsigned int i=0;i<v[x].size();i++)
    {
        y=v[x][i].first;cost=v[x][i].second;
        if(cost<d[y])
        {
            d[y]=cost;
            if(!s[y])
                push(y);
            else
                up(poz[y]);
            s[y]=x;
        }
    }
}
int main()
{
    FILE *fin,*fout;
    fin=fopen("apm.in","r");
    fout=fopen("apm.out","w");
    int n,m,x,y,c;
    fscanf(fin,"%d%d",&n,&m);
    for(int i=0;i<m;i++)
    {
        fscanf(fin,"%d%d%d",&x,&y,&c);
        v[x].push_back(make_pair(y,c));
        v[y].push_back(make_pair(x,c));
    }
    for(int i=2;i<=n;i++)
        d[i]=INF;
    d[1]=-INF;ans=INF;
    n--;adauga_in_apm(1);
    for(int i=0;i<n;i++)
    {
        x=heap[1];pop();
        sol.push_back(make_pair(s[x],x));
        adauga_in_apm(x);
    }
    fprintf(fout,"%d\n%d\n",ans,n);
    for(unsigned int i=0;i<sol.size();i++)
        fprintf(fout,"%d %d\n",sol[i].first,sol[i].second);
    fclose(fin);
    fclose(fout);
    return 0;
}