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<utility>
#include<vector>
#include<algorithm>
#define loop(i,a,b) for(int i=a;i<b;i++)
#define rep(i,a) loop(i,0,a)
#define pb push_back
#define all(v) v.begin(),v.end()
using namespace std;
typedef pair<int,int> pii;
typedef pair<int,pii> piii;
int parent[10010];

int find(int a){
	if(parent[a]==a)return a;
	else return parent[a]=find(parent[a]);
}

void unite(int a,int b){
	parent[find(a)]=find(b);
	find(a);find(b);
}

int main(){
	int n,m,a,b,c;
	cin>>n>>m;
	vector<piii> edge;
	rep(i,m){
		cin>>a>>b>>c;
		edge.pb(piii(c,pii(a,b)));
	}
	rep(i,n)parent[i]=i;
	sort(all(edge));
	int ans=0;
	rep(i,edge.size()){
		int a=edge[i].second.first,b=edge[i].second.second;
		if(find(a)==find(b))continue;
		ans+=edge[i].first;
		unite(a,b);
	}
	cout<<ans<<endl;
	return 0;
}