# include <bits/stdc++.h>
using namespace std;
int mp[5110][5110];
const int inf = 1e6+10;
int d[10010110],vis[10101010];
void prim(int n)
{
	for(int i = 1;i <= n;i++)
	{
		d[i] = inf;
	}
	d[1] = 0;
	int ret = 0;
	for(int step = 1;step <= n;step++)
	{
		int mi = inf;
		int id = -1;
		for(int i = 1;i <= n;i++)
		{
			if(!vis[i] && d[i] < mi)
			{
				mi = d[i];
				id = i;
			}
		}
		ret += mi;
		if(id == -1)
		{
			printf("orz\n");
			exit(0);
		}
		vis[id] = 1;
		for(int i = 1;i <= n;i++)
		{
			if(!vis[i] && mp[id][i] < d[i])
			{
				d[i] = mp[id][i];
			}
		}
	}
	printf("%d\n",ret);
}
int main (){
	int n,m;
	scanf("%d%d",&n,&m);
	for(int i = 1;i <= n;i++)
	{
		for(int j = 1;j <= m;j++)
		{
			mp[i][j] = inf;
		}
	}
    int a,b,c;
	for(int i = 1;i <= m;i++)
	{
		
		scanf("%d%d%d",&a,&b,&c);
		if(mp[a][b] > c)
		{
			mp[a][b] = mp[b][a] = c;
		}
	}
	prim(n);
	return 0;
}