#include<cstdio>
#include<algorithm>
#include<vector>
#define x first
#define y second
using namespace std;
int n,m,cost,c;
vector< pair<int, pair<int,int> > > a;   
pair<int,int> aux;				
vector<int> b;		
vector< pair<int,int> > sol;
int un(int x)
{
    if(b[x]==x) return x;
    b[x] = un( b[x] );
    return b[x];
}
int main ()
{
    freopen("apm.in","rt",stdin);
    scanf("%d%d",&n,&m);
    for(int i=0;i<m;++i) 
	{
		scanf("%d%d%d",&aux.x,&aux.y,&c);
		a.push_back(make_pair(c,aux));
	}
    sort(a.begin(),a.end());
	
    for(int i=0;i<n;++i) b.push_back(i);
	
    for(int i=0;i<m;++i)
	{
        if( un(a[i].y.x)!=un(a[i].y.y) )
		{
            b[ un(a[i].y.y) ]= un(a[i].y.x);
            sol.push_back(a[i].y);
            cost+=a[i].x;
        }
    }
    printf("Costul minim este = %d\n",cost);
    return 0;
}