#include<bits/stdc++.h>
using namespace std;
const int X = 20110;
struct node{
	int u,v,c;
}G[X];
int f[X];
int n,m;

bool cmp(node a,node b){
	return a.c < b.c;
}

int find_f(int x){
	return x == f[x]?x:f[x] = find_f(f[x]);
}

void join(int fx,int fy){
	f[fy] = f[fx];
}

void init(){
	cin>>n>>m;
	for(int i = 1;i <= m;i++){
		cin>>G[i].u>>G[i].v>>G[i].c;
	}
	sort(G + 1,G + 1 + m,cmp);
	for(int i = 0;i <= n;i++){
		f[i] = i;
	}
}

int main(){
	int ans = 0,i = 1;
	init();
	for(int j = 1;i <= n - 1&&j <= m;){
		int fx = find_f(G[j].u),
			fy = find_f(G[j].v);
		if(fx == fy){
			j++;
		}
		else{
			i++;
			join(fx,fy);
			ans += G[j].c;
		}
	}
	if(i == n + 1){
		cout<<"orz"<<endl;
	}
	else{
		cout<<ans<<endl;
	}
	return 0;
}