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 unionFind{
  vector<int>par;

  unionFind(int N):par(N){
    for(int i=0;i<N;i++)par[i] = i;
  }

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

  void unite(int x,int y){
    int rx = root(x);
    int ry = root(y);
    if(rx == ry)return;
    else par[rx]=ry;
  }

  bool same(int x,int y){
    return root(x)==root(y);
  }
};

int main(){
  int v,e;
  cin >> v >> e;
  int s,t,w;
  vector<pair<int,pair<int,int> > >path(e);
  int i;
  for(i=0;i<e;i++){
    cin >> s >> t >> w;
    path[i] = make_pair(w,make_pair(s,t));
  }
  unionFind unif = unionFind(v);
  sort(path.begin(),path.end());

  long length = 0;
  for(i=0;i<e;i++){
    int x = path[i].second.first;
    int y = path[i].second.second;
    if(!unif.same(x,y)){
      unif.unite(x,y);
      length += path[i].first;
    }
  }
  cout << length << endl;

}