#include<cstdio>
#include<vector>
#define INF 1000000000
using namespace std;
vector< pair< int , int > >L[200100];
int n,m,i,j,a,b,c,s,nr,poz,p,ok,dh,d[200100],v[200100],sl[200100],sc[200100],h[400100],x[400100],t[400100];
FILE *f,*g;
void chg(int &x,int &y){
    int aux=x;
    x=y;
    y=aux;
}
void hdel(){
    h[1]=h[dh];
    dh--;
    p=1;
    c=2;
    x[ h[1] ]=1;
    while(c<=dh){
        if( d[ h[c] ] > d[ h[ c+1 ] ] && c < dh )
            c++;
        if( d[ h[c] ] < d[ h[p] ] ){
            chg( h[c],h[p] );
            x[ h[c] ]=c;
            x[ h[p] ]=p;
            p=c;
            c*=2;
        }
        else
            break;
    }
}
void hupd(int poz){
    c=poz;
    p=poz/2;
    while(p){
        if( d[ h[c] ] < d[ h[p] ]  ){
            chg( h[c],h[p] );
            x[ h[c] ]=c;
            x[ h[p] ]=p;
            c=p;
            p/=2;
        }
        else
            break;
    }
}
int main(){
    f=fopen("apm.in","r");
    g=fopen("apm.out","w");
    fscanf(f,"%d%d",&n,&m);
    for(i=1;i<=m;i++){
        fscanf(f,"%d%d%d",&a,&b,&c);
        L[a].push_back( make_pair(b,c) );
        L[b].push_back( make_pair(a,c) );
    }
    for(i=2;i<=n;i++){
        d[i]=INF;
    }
    dh=1;
    h[1]=1;
    x[1]=1;
    while(dh){
        poz=h[1];
        hdel();
        s+=d[poz];
        sl[++nr]=t[poz];
        sc[nr]=poz;
        v[poz]=1;
        for(i=0;i<L[poz].size();i++){
            a=L[poz][i].first;
            b=L[poz][i].second;
            if(  d[a] > b ){
                if( d[a] == INF )
                    ok=1;
                else
                    ok=0;
                d[a]=b;
                t[a]=poz;
                if( ok ){
                    h[++dh]=a;
                    x[a]=dh;
                    hupd(dh);
                }
                else
                    hupd(x[a]);
            }
        }
    }
    fprintf(g,"%d\n%d\n",s,nr-1);
    for(i=2;i<=nr;i++){
        fprintf(g,"%d %d\n",sl[i],sc[i]);
    }




    fclose(f);
    fclose(g);
    return 0;
}