#include <cstdio>
#define NMAX 200001
#define MMAX 400001

//min heap
using namespace std;
struct Muchie
{
    int x,y,c;
} G[NMAX];
int n,m;
int H[MMAX];
FILE * fout=fopen("heapuri.out","w");
long long int cost;
int A[NMAX];//retin indicii muchiilor selectate in APM
int h[NMAX];//inaltimea arborelui cu radacina i
int tata[NMAX];


void citire();
//void inserare(int H[NMAX], int& n, int x);
//void afisare_heap(int H[NMAX], int n);
void creare_heap_inserare(int H[NMAX], int &n);
void combinare(int H[NMAX], int m, int i);
void creare_heap_combinare(int H[NMAX], int &n);
int extragere(int H[NMAX], int &n);
int Find(int x);
void Union(int i, int j);
void afisare();
int main()
{
    int i,nr=0,mmin,cx,cy;
    citire();
    creare_heap_combinare(H,m);

    while(nr<n-1)
    {
        mmin=extragere(H,m);
        cx=Find(G[mmin].x);
        cy=Find(G[mmin].y);
        if(cx!=cy)
        {
            nr++;
            A[nr]=mmin;
            cost+=G[mmin].c;
            Union(cx,cy);
        }
    }


    fclose(fout);

    return 0;
}

void afisare()
{
    int i;
    fprintf(fout, "%d\n", cost);
    fprintf(fout, "%d\n", n-1);

    for(i=1; i<n; i++)
        fprintf(fout, "%d %d\n", G[A[i]].x, G[A[i]].y);
    fclose(fout);

}

void inserare(int H[NMAX], int& n, int x)
//se insereaza x in heapul H care are n elemente
{
    int fiu,tata;
    n++;
    fiu=n;
    tata=fiu/2;// tata=fiu>>1;
    while(tata!=0 && H[tata]>x)
    {
        H[fiu]=H[tata];
        fiu=tata;
        tata=fiu/2; // tata=fiu>>1;
    }
    H[fiu]=x;
}



void afisare_heap(int H[NMAX], int n)
{
    int i;

    for(i=1; i<=n; i++)
        fprintf(fout,"%d ",H[i]);
    fprintf(fout,"\n");
}


void combinare(int H[NMAX], int n, int i)
{
    int x=H[i],tata,fiu;
    tata=i;
    fiu=i*2;
    while   (fiu<=n)
    {
        if(fiu+1<=n && G[H[fiu+1]].c<G[H[fiu]].c) fiu++;

        if(G[H[fiu]].c>G[x].c)
        {
            H[tata]=H[fiu];
            tata=fiu;
            fiu=tata*2;
        }
        else break;
    }
    H[tata]=x;
}

void creare_heap_combinare(int H[NMAX], int &n)
{
    FILE* fin=fopen("heapuri.in","r");
    int nr,i,x;
    n=0;
    for(i=1;i<=n;i++) H[i]=0;
    for(i=n/2; i>0; i--)
        combinare(H,n,i);
}


int extragere(int H[NMAX], int &n)
{
    int min=H[1];
    H[1]=H[n--];
    combinare(H,n,1);
    return min;
}






void citire()
{

    FILE* fin=fopen("apm.in","r");
//    ifstream fin("apm.in");
    int i;
    fscanf(fin,"%d",&n,&m);

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

        fscanf(fin,"%d",&G[i].x,&G[i].y,&G[i].c);
        //fin>>G[i].x>>G[i].y>>G[i].c;
    }


}

int Find(int x)
{
    int rad=x,aux;
    while(tata[rad]) rad=tata[rad];
    while(tata[x])
    {
        aux=tata[x];
        tata[x]=rad;
        x=aux;
    }
    return rad;

}
void Union(int i, int j)// j fiul al lui i,j si i radacini
{

    if(h[i]<h[j]) //i devine fiul al lui j
        tata[i]=j;
    else
    {
        tata[j]=i;
        if(h[i]==h[j]) h[i]++;
    }


}