//
// Created by hy on 2019/7/28.
//
#include<algorithm>
#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
#include <set>
using namespace std;
typedef long long ll;
const int maxn=2e5+10;
ll father[maxn];
ll n,ans,point,m;
struct Node{
    int u,v,w;
    bool operator<(const Node other)const{
        return this->w<other.w;
    }
}node[maxn];
ll find(ll x)
{
    if(x==father[x])
        return x;
    return father[x]=find(father[x]);
}
void kru()
{
    sort(node,node+m);
    for(int i=0;i<m;i++)
    {
        int uu=find(node[i].u);
        int vv=find(node[i].v);
        if(uu==vv)
            continue;
        else
        {
            father[uu]=vv;
            ans+=node[i].w;
            point++;
            if(point==n-1)
                break;
        }

    }
}
int main()
{
    scanf("%lld%lld",&n,&m);
    for(int i=0;i<=n;i++)
        father[i]=i;
    for(int i=0;i<m;i++)
        scanf("%lld%lld%lld",&node[i].u,&node[i].v,&node[i].w);
    ans=0,point=0;
    kru();
    printf("%lld",ans);
    if(point!=n-1)
        printf("orz");
    return 0;
}