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.PriorityQueue;
import java.util.Scanner;

public class Main {
	
	static PriorityQueue<Edge> pq=new PriorityQueue<>();
	static int V, E;
	static int[] par;
	
	static class Edge implements Comparable<Edge>{
		int u, v, cost;
		Edge(int u, int v, int cost){
			this.u=u;
			this.v=v;
			this.cost=cost;
		}
		public int compareTo(Edge e) {
			return this.cost-e.cost;
		}
	}
	
	static void init(int N) {//初期化
		for(int i=0; i<N; i++) {
			par[i]=i;
		}
	}
	
	static int root(int x) {//親を求める
		if(par[x]==x) {
			return x;
		}
		return par[x]=root(par[x]);
	}
	
	static boolean same(int x, int y) {//判定(同グループかどうか)
		return (root(x)==root(y));
	}
	
	static void unite(int x, int y) {//まとめる
		par[root(x)]=root(y);
	}
	
	static int kraskal() {
		init(V);
		int res=0;
		for(int i=0; i<E; i++) {
			Edge e=pq.poll();
			if(!same(e.u, e.v)) {
				unite(e.u, e.v);
				res+=e.cost;
			}
		}
		return res;
	}
	
	
	public static void main(String[] args) {
		try(Scanner sc = new Scanner(System.in)){
			V=sc.nextInt();
			E=sc.nextInt();
			par=new int[V];
			for(int i=0; i<E; i++) {
				int s=sc.nextInt();
				int t=sc.nextInt();
				int w=sc.nextInt();
				pq.add(new Edge(s, t, w));
			}
			System.out.println(kraskal());
			
		}
	}
}