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;

struct Edge{
	  int s,t,w;
	  Edge(int si, int ti, int wi){
			s = si; t = ti; w = wi;
	  }
	  bool operator < (const Edge& e) const {
			return w < e.w;
	  }
	  bool operator > (const Edge& e) const {
			return w > e.w;
	  }
	  void print(){
			cout << s << "->" << t << ":" << w << endl;
	  }
};

typedef vector<vector<Edge> > Graph;

int prim(Graph& G){

	  priority_queue<Edge, vector<Edge>, greater<Edge> > q;
	  vector<int> used(G.size(),0);
	  int num_used=0, ans=0;
	  
	  for(Edge e : G[0])	q.push(e);
	  used[0] = 1; num_used++;
	  
	  while(q.size()){
			Edge e = q.top(); q.pop();
			if(used[e.t] == 1) continue;
			used[e.t] = 1; num_used++; ans += e.w;
			if(num_used == G.size()) break;
			for(Edge ne : G[e.t])
				  if(used[ne.t] != 1)
						q.push(ne);
	  }
	  return ans;
}


int main(){

	  int V,E; cin >> V >> E;
	  Graph G(V);
	  for(int i=0; i<E; i++){
			int s,t,w; cin >> s >> t >> w;
			G[s].push_back( Edge(s,t,w) );
			G[t].push_back( Edge(t,s,w) );
	  }
	  cout << prim(G) << endl;
	  
}