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 <cstdio>
#include <iostream>
#include <algorithm>
#include <vector>
#include <set>
using namespace std;
const int maxx=100010;
const int inf=0x7fffffff;
int v,e,ans=0;
class edge{
	public:
		int source,target,cost;
		edge(int source,int target,int cost):
			source(source),target(target),cost(cost){}
		bool operator < (const edge &e ) const {
			return cost<e.cost;
		}	
};

vector<edge > A;
int pre[maxx];

int find(int u){
	if(pre[u]!=u) pre[u]=find(pre[u]);
	return pre[u];	
}

void hebing(int x,int y){
	if(find(x)!=find(y)) pre[find(y)]=find(x);
	find(y);
	return ;
}

int main (){
	cin>>v>>e;
	if(e==0) {
		cout<<"0"<<endl;return 0;
	}
	int x,y,z;
	while(e--){
		cin>>x>>y>>z;
		A.push_back(edge(x,y,z));
	}
	sort(A.begin(),A.end());
	for(int i=0;i<v;i++) pre[i]=i;
	for(int i=0;i<A.size();i++){
//		for(int i=0;i<v;i++){
//			cout<<i<<"  "<<pre[i]<<endl;
//		}cout<<endl;
		if(find(A[i].source)!=find(A[i].target)) {
			hebing(A[i].source,A[i].target);
			ans+=A[i].cost;
			//cout<<A[i].source<<"  "<<A[i].target<<"  "<<A[i].cost<<endl;
		}
	}
	cout<<ans<<endl;
	return 0;
	
}