import java.util.*;

class Node implements Comparable<Node> {
    int node;
    int dist;

    Node(int node, int dist) {
        this.node = node;
        this.dist = dist;
    }

    @Override
    public int compareTo(Node other) {
        return this.dist - other.dist;
    }
}

public class _1647_2 {
    static void prim(ArrayList<ArrayList<Node>> graph, int V) {
        boolean[] visited = new boolean[V+1];
        PriorityQueue<Node> pq = new PriorityQueue<>();
        pq.add(new Node(1, 0));

        int cnt = 0, total_dist = 0, max_dist = 0;

        while(!pq.isEmpty()) {
            Node now = pq.poll();
            int current_node = now.node, current_dist = now.dist;

            if(visited[current_node]) continue;

            visited[current_node] = true;
            total_dist += current_dist;
            max_dist = Math.max(max_dist, current_dist);
            cnt += 1;

            if(cnt == V) break;

            for(Node next : graph.get(current_node)) {
                if(!visited[next.node]) {
                    pq.add(next);
                }
            }
        }

        System.out.println(total_dist - max_dist);
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt(), M = sc.nextInt();
        
        if(N==2) {
            System.out.println(0);
            sc.close();
            return ;
        }

        ArrayList<ArrayList<Node>> graph = new ArrayList<>();
        for(int i=0; i<=N; i++) graph.add(new ArrayList<>());

        for(int i=0; i<M; i++) {
            int A = sc.nextInt(), B = sc.nextInt(), C = sc.nextInt();
            graph.get(A).add(new Node(B, C));
            graph.get(B).add(new Node(A, C));
        }
        sc.close();

        prim(graph, N);
    }
}