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 <vector>
#include <queue>
using namespace std;


typedef pair<int,int> pii;
vector< vector<pii> > edges;
vector<bool> used;

int solve() {
    priority_queue<pii, vector<pii>, greater<pii> > que;
    for(int i=0; i<used.size(); i++)used[i] = false;
  
    que.push( make_pair(0,0) );
    int ret = 0;
    
    while(!que.empty()) {
        int cost = que.top().first, v = que.top().second;
        que.pop();
	
        if(used[v]) continue;
        used[v] = true;
        ret += cost;
        for(int i = 0; i < edges[v].size(); i++)
            que.push(pii(edges[v][i].first, edges[v][i].second));
    }
    return ret;
}


int main(){

  int V,E;
  
  cin >> V >> E;

  edges.resize(V);
  
  used.resize(V);

  for(int i=0; i<E; i++){
    int s,t,w;
    cin >> s >> t >> w;
    edges[s].push_back( make_pair(w,t) );
    edges[t].push_back( make_pair(w,s) );
  }

  cout << solve() << endl;

  return 0;
}