#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;

ifstream f("apm.in");
ofstream g("apm.out");

int viz[101];
int i, j, n, m, a, b, c;

struct muchie {int nod1; int nod2; int cost;};//muchie nod1 - nod2
muchie arb[400002];

bool compare(muchie lhs, muchie rhs)    {
    return (lhs.cost < rhs.cost);
}

int main()
{
    f>>n>>m;
    for (i=0;i<m;i++)
        f>>arb[i].nod1>>arb[i].nod2>>arb[i].cost;
    sort (arb, arb+m, compare);
    int nr=1, ct;
    viz[arb[i].nod1] = viz[arb[i].nod2] = 1;
    ct = arb[1].cost;//ct = cost total
    while (nr!=n-1) {
        i=1;
        while (viz[arb[i].nod1] + viz[arb[i].nod2] != 1)
            i++;
        viz[arb[i].nod1] = 1;
        viz[arb[i].nod2] = 1;
        nr++;
        ct = ct + arb[i].cost;
    }
    g<<ct;
    return 0;
}