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 CPP):

Solution:
#include<iostream>
#include<cstdio>
#include<vector>
#include<algorithm>
using namespace std;
struct edge{int from,to,cost;};
bool comp(const edge& e1,const edge& e2){
	return e1.cost<e2.cost;
}
int V,E;
edge G[100000];
//Union-Find
int par[10000];
int Rank[10000];
void init()
{
	for(int i=0;i<V;i++){
		par[i]=i;
		Rank[i]=0;
	}
}
int find(int x)
{
	if(x==par[x])return x;
	return par[x]=find(par[x]);
}
void unite(int x,int y){
	x=find(x);
	y=find(y);
	if(x==y)return ;

	if(Rank[x]<Rank[y]){
		par[x]=y;
	}
	else{
		par[y]=x;

	}
	if(Rank[x]==Rank[y])Rank[x]++;
}
bool same(int x,int y){
	return find(x)==find(y);
}
int kkk()
{
	int ans=0;
	for(int i=0;i<E;i++){
		//printf("%d\n",same(G[i].from,G[i].to));
		//printf("%d %d\n",G[i].from,G[i].to);
		if(!same(G[i].from,G[i].to)){
			unite(G[i].from,G[i].to);
			ans+=G[i].cost;
		}
	}
	return ans;
}
int main()
{
	scanf("%d%d",&V,&E);
	for(int i=0;i<E;i++){
		int a,b,c;
		scanf("%d%d%d",&a,&b,&c);
		edge e1={a,b,c};
		G[i]=e1;
	}
	sort(G,G+E,comp);
	init();
	printf("%d\n",kkk());
	return 0;
}