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>
using namespace std;
int V,E;
int par[10000],rnk[10000];

int find(int x){
    if(par[x]==x)return x;
    else return par[x]=find(par[x]);
}
void unite(int x,int y){
    x=find(x);
    y=find(y);
    if(rnk[x]<rnk[y])par[x]=y;
    else{
        par[y]=x;
        if(rnk[x]==rnk[y])rnk[x]++;
    }
}
bool same(int x,int y){
    return find(x)==find(y);
}
class edge{
    public:
    int s,t,cost;
    bool operator <(const edge&n)const{
        return cost<n.cost;
    }
    
};

int main(void){
  cin>>V>>E;
  edge x[E];
  for(int i=0;i<V;i++){
      par[i]=i;
      rnk[i]=0;
  }
  int ans=0;
  for(int i=0;i<E;i++){
      cin>>x[i].s>>x[i].t>>x[i].cost;
  }
  sort(x,x+E);
  for(int i=0;i<E;i++){
      if(!same(x[i].s,x[i].t)){
          unite(x[i].s,x[i].t);
          ans+=x[i].cost;
      }
  }
  cout<<ans<<endl;
    
}