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 {

	private class Edge implements Comparable<Edge> {

		int from;
		int to;
		int weight;

		public Edge(int a, int b, int c) {
			from = a;
			to = b;
			weight = c;
		}

		@Override
		public int compareTo(Edge other) {
			return this.weight - other.weight;

		}

	}

	static int vertex;
	static int edge;
	static ArrayList<Edge>[] graph;
	static boolean[] visited;

	@SuppressWarnings("unchecked")
	public static void main(String[] args) {
		Main obj = new Main();
		Scanner sc = new Scanner(System.in);
		vertex = sc.nextInt();
		edge = sc.nextInt();
		visited = new boolean[vertex];
		graph = new ArrayList[vertex];
		for (int i = 0; i < graph.length; i++) {
			graph[i] = new ArrayList<Edge>();
		}
		for (int i = 0; i < edge; i++) {
			int a = sc.nextInt();
			int b = sc.nextInt();
			int c = sc.nextInt();
			graph[a].add(obj.new Edge(a, b, c));
			graph[b].add(obj.new Edge(b, a, c));
		}
		PriorityQueue<Edge> pq = new PriorityQueue<Edge>();
		for (Edge e : graph[0]) {
			pq.offer(e);
		}
		visited[0] = true;
		int sum = 0;
		while (!pq.isEmpty()) {
			Edge e = pq.poll();
			if (visited[e.to]) {
				continue;
			}
			visited[e.to] = true;
			sum += e.weight;
			for (Edge f : graph[e.to]) {
				if (!visited[f.to]) {
					pq.offer(f);
				}
			}
		}
		System.out.println(sum);
	}
}