Problem: Find the sum of weights of edges of the Minimum Spanning Tree for a given weighted undirected graph G = (V, E).

Constraints

* 1 ≤ |V| ≤ 10,000
* 0 ≤ |E| ≤ 100,000
* 0 ≤ wi ≤ 10,000
* The graph is connected
* There are no parallel edges
* There are no self-loops

Input


|V| |E|
s0 t0 w0
s1 t1 w1
:
s|E|-1 t|E|-1 w|E|-1


, where |V| is the number of vertices and |E| is the number of edges in the graph. The graph vertices are named with the numbers 0, 1,..., |V|-1 respectively.

si and ti represent source and target verticess of i-th edge (undirected) and wi represents the weight of the i-th edge.

Output

Print the sum of the weights of the Minimum Spanning Tree.

Examples

Input

4 6
0 1 2
1 2 1
2 3 1
3 0 1
0 2 3
1 3 5


Output

3


Input

6 9
0 1 1
0 2 3
1 2 1
1 3 7
2 4 1
1 4 3
3 4 1
3 5 1
4 5 6


Output

5

Solution (in JAVA):

Solution:
import java.util.*;

public class Main {
    int n, m;
    ArrayList<ArrayList<Edge>> edges;

    public static void main(String[] args) {
        Main p = new Main();
        p.read();
        p.solve();
    }

    void read() {
        Scanner sc = new Scanner(System.in);
        n = sc.nextInt();
        m = sc.nextInt();
        edges = new ArrayList<>(n);
        for (int i = 0; i < n; i++) {
            edges.add(new ArrayList<>());
        }
        for (int i = 0; i < m; i++) {
            int src = sc.nextInt();
            int trg = sc.nextInt();
            int cost = sc.nextInt();
            edges.get(src).add(new Edge(trg, cost));
            edges.get(trg).add(new Edge(src, cost));
        }
    }

    void solve() {
        boolean[] tree = new boolean[n];
        long ans = 0L;
        PriorityQueue<Edge> queue = new PriorityQueue<>(new Comparator<Edge>() {
            @Override
            public int compare(Edge edge, Edge t1) {
                return Integer.compare(edge.cost, t1.cost);
            }
        });
        tree[0] = true;
        for (Edge e: edges.get(0)) {
            queue.add(e);
        }
        while (!queue.isEmpty()) {
            Edge e = queue.poll();
            if (tree[e.to])
                continue;
            ans += e.cost;
            tree[e.to] = true;
            for (Edge _e: edges.get(e.to)) {
                if (!tree[_e.to])
                    queue.add(_e);
            }
        }
        System.out.println(ans);
    }
}

class Edge {
    int to, cost;
    Edge(int to, int cost) {
        this.to = to;
        this.cost = cost;
    }
}