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 <string>
#include <algorithm>
#include <map>
#include <utility>
#include <queue>

using namespace std;
using llong = long long;
using P = pair<int,int>;

map<int,int> graph[10000];
bool visited[10000];

int main(){
  int N , M ;
  cin >> N >> M;
  for(int i=0;i<M;++i){
    int s,t,w;
    cin >> s >> t >> w;
    graph[s][t] = w;
    graph[t][s] = w;
  }
  priority_queue<P,vector<P>,greater<P> > Q;
  Q.push(P(0,0));
  int sum = 0;
  while(!Q.empty()){
    int cost = Q.top().first , v = Q.top().second;
    Q.pop();
    if(visited[v]) continue;
    visited[v] = true;
    sum += cost;
    for(const auto &n:graph[v]){
      Q.push(P(n.second,n.first));
    }
  }

  cout << sum << endl;
  return 0;
}