#include <bits/stdc++.h>
using namespace std;

#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define pb push_back
#define x first
#define y second
#define FOR(i, a, b) for(int i = (a); i < (b); i++)
#define RFOR(i, a, b) for(int i = (a) - 1; i >= (b); i--)

typedef long long ll;
typedef double db;
typedef long double LD;
typedef pair<int, int> pii;
typedef pair<db, db> pdd;
typedef pair<ll, ll> pll;

const int N = 1e5 + 47;
int par[N];

struct Edge
{
	int s, d;
	ll w;
	
	Edge(){}
	Edge (int ss, int dd, ll ww)
	{
		s = ss;
		d = dd;
		w = ww;
	}
	bool operator<(const Edge& oth)
	{
		return this->w < oth.w;
	}
};

int find_set(int v) {
    if (v == par[v])
        return v;
    return par[v] = find_set(par[v]);
}

bool union_sets(int a, int b) {
    a = find_set(a);
    b = find_set(b);
    if (a != b)
    {
		par[b] = a;
		return true;
	}
    return false;
}

int solve()
{
	int n, m;
	if (!(cin >> n >> m))
		return 1;
	
	iota(par, par + N, 0);
	vector<Edge> ed(m);
	FOR (i, 0, m)
	{
		int v, u;
		ll w;
		cin >> v >> u >> w;
		--v;
		--u;
		ed[i] = Edge(v, u, w);
	}
	
	sort(all(ed));
	ed.erase(ed.begin());
	ll ans = 0;
	FOR (i, 0, m - 1)
	{
		if (union_sets(ed[i].s, ed[i].d))
			ans += ed[i].w;
	}
	cout << ans << '\n';
	
	return 0;
}

int32_t main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	int TET = 1e9;
	//cin >> TET;
	for (int i = 1; i <= TET; i++)
	{
		if (solve())
		{
			break;
		}
		#ifdef ONPC
			cerr << "_____________________________\n";
		#endif
	}
	#ifdef ONPC
		cerr << "\nfinished in " << clock() * 1.0 / CLOCKS_PER_SEC << " sec\n";
	#endif
	return 0;
}