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;
typedef pair<int,int> P;

struct edge{
  int to,cost;
};

vector< edge > G[10000];
int d[10000];
int visited[10000];

int V,E;

int main(){
  cin>>V>>E;
  for(int i=0;i<E;i++){
    int a,b,c;
    cin>>a>>b>>c;
    G[a].push_back( (edge){b,c} );
    G[b].push_back( (edge){a,c} );
  }
  for(int i=0;i<V;i++){
    d[i]=1e9;
    visited[i]=0;
  }
  d[0]=0;
  priority_queue< P , vector<P> , greater<P> > Q;
  Q.push( P(0,0) );
  
  while(!Q.empty()){
    P p=Q.top();
    Q.pop();
    int pos=p.second;
    int cost=p.first;
    visited[pos]=1;
    if(d[pos]<cost)continue;
    for(int i=0;i<(int)G[pos].size();i++){
      edge e=G[pos][i];
      if(visited[e.to])continue;
      if(d[e.to]>e.cost){
        d[e.to]=e.cost;
        Q.push(P(e.cost,e.to));
      }
    }
  }
  int ans=0;
  for(int i=0;i<V;i++)ans+=d[i];
  cout<<ans<<endl;
  return 0;
}