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

struct edge{
  int from, to, cost;
};

bool operator<(const edge &a, const edge &b){
  return a.cost < b.cost;
}

vector<edge> g;
int par[10000];

int find(int x){
  if(par[x] == x) return x;
  return par[x] = find(par[x]);
}

bool uni(int x, int y){
  x = find(x);
  y = find(y);
  if(x == y) return false;
  par[x] = y;
  return true;
}

int main(){

  int v, e, s, t, w;
  cin >> v >> e;
  for(int i = 0; i < v; i++) par[i] = i;
  for(int i = 0; i < e; i++){
    cin >> s >> t >> w;
    g.push_back((edge){s, t, w});
  }
  sort(g.begin(), g.end());
  int sum = 0;
  for(int i = 0; i < g.size(); i++){
    edge e = g[i];
    if(uni(e.from, e.to)) sum += e.cost;
  }
  cout << sum << endl;
  return 0;
}