#include <iostream>
#include <cstring>
#include <queue>
using namespace std;


struct edge{
	int s,t,s_next,t_next,len;
	bool operator < (const edge a)const{
		return len>a.len;
	}
};


int main(){
	int n,m;
	long long ans=0;
	bool can_build=true;
	cin>>n>>m;
	bool vis[n];
	memset(vis,false,sizeof(vis));
	int edge_header[n];
	memset(edge_header,-1,sizeof(edge_header));
	edge edges[m];
	for(int i=0;i<m;i++){
		int s,t,len;
		cin>>s>>t>>len;
		s--;t--;
		edges[i].s = s;
		edges[i].t = t;
		edges[i].len = len;
		edges[i].s_next = edge_header[s];
		edges[i].t_next = edge_header[t];
		edge_header[s] = edge_header[t] = i;
	}
	priority_queue<edge> q;
	int now=0;
//	vis[now] = true;
	for(int i=0;i<n-1;i++){
		if(!vis[now]){
			vis[now] = true;
			int next = edge_header[now];
			while(next != -1){
				if(!(vis[edges[next].s]  &&  vis[edges[next].t]))
					q.push(edges[next]);
				if(edges[next].s == now)
					next = edges[next].s_next;
				else
					next = edges[next].t_next;
			}
		}
		while(vis[q.top().s]  &&  vis[q.top().t]){ q.pop();}
		if(q.empty()){
			can_build = false;
			break;
		}
		ans += q.top().len;
		if(q.top().s == now){
//			vis[q.top().t] = true;
			now = q.top().t;
		}
		else{
//			vis[q.top().s] = true;
			now = q.top().s;
		}
		q.pop();
	}
	if(can_build)
		cout<<ans;
	else
		cout<<"orz";
	return 0;
}