#include<iostream>

#include<algorithm>

using namespace std;

int unf[1001];

struct info{

int a, b, c;

};

bool asc(info a, info b){

return a.c < b.c;

}

int Find(int v){

if(v == unf[v]) return v;

else return unf[v] = Find(unf[v]);

}

void Union(int a, int b){

a = Find(a);

b = Find(b);

if(a != b) unf[a] = b;

}

int main(){

ios_base::sync_with_stdio(false);

cin.tie(NULL);

freopen("input.txt", "rt", stdin);

info abc[1001];

int v, e, a, b, c, cost = 0;

cin>>v>>e;

for(int i = 1; i <= e; i++){

unf[i] = i;

}

for(int i = 0; i < e; i++){

cin>>a>>b>>c;

abc[i].a = a;

abc[i].b = b;

abc[i].c = c;

}

sort(abc, abc + e, asc);

for(int i = 0; i < e; i++){

// cout<<abc[i].a<<" "<<abc[i].b<<" "<<abc[i].c<<"\n";

if(Find(abc[i].a) != Find(abc[i].b)){

Union(abc[i].a, abc[i].b);

cost += abc[i].c;

}else{

continue;

}

}

cout<<cost<<"\n";

return 0;

}