prims

#include<bits/stdc++.h>
using namespace std;
#define pii pair<long long,int>
vector<pii>v[100007];
bool vis[100007];
long long solve(int x)
{
    int y;
    long long min_cost=0;
    priority_queue<pii>p;
    p.push({0,x});
    while(!p.empty())
    {
        pii p1=p.top();
        p.pop();
        x=p1.second;
        if(vis[x])continue;
        min_cost-=p1.first;
        vis[x]=true;

        for(int i=0;i<v[x].size();i++)
        {
            if(!vis[v[x][i].second])
            {
                p.push({-1*v[x][i].first,v[x][i].second});
            }
        }
    }
    return min_cost;
}

int main()
{

    int x,y,nodes,edges;
    long long cost;
    cin>>nodes>>edges;
    for(int i=0;i<edges;i++)
    {
        cin>>x>>y>>cost;
        v[x].push_back({cost,y});
        v[y].push_back({cost,x});
    }
    cout<<solve(1)<<endl;
    return 0;
}