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<bits/stdc++.h>
using namespace std;
typedef tuple<int,int,int>T;
typedef vector<T>VT;
int main(void){
	int v,e;
	int s,t,w;
	VT vt;
	T tt;
	int par[10001],ran[10001];
	int x,y;
	int sum;
	int i,j;
	cin>>v>>e;
	for(i=0;i<e;i++){
		cin>>s>>t>>w;
		get<0>(tt)=w;
		get<1>(tt)=s;
		get<2>(tt)=t;
		vt.push_back(tt);
	}
	sort(vt.begin(),vt.end());
	for(i=0;i<v;i++){
		par[i]=i;
		ran[i]=0;
	}
	sum=0;
	for(i=0;i<e;i++){
		x=get<1>(vt[i]);
		y=get<2>(vt[i]);
		while(x!=par[x])	x=par[x];
		while(y!=par[y])	y=par[y];
		if(x!=y){
			if		(ran[x]<ran[y])	par[x]=y;
			else if	(ran[x]>ran[y])	par[y]=x;
			else{	
				par[x]=y;
				ran[y]++;
			}
			sum+=get<0>(vt[i]);
		}
	}
	cout<<sum<<endl;
	return 0;
}