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<algorithm>
#include<queue>

using namespace std;
#define MV 10001
#define INF 1e9

struct edge{int to,cost;};
vector <edge> G[MV];
bool used[MV];
int V,E;
int d[MV];

int prim(){  
    for(int i=0;i<V;i++){
        d[i] = INF;
        used[i]=false;
    }
    d[0]=0;
    used[0]=true;
  
    for(int i=0;i<G[0].size();i++){
        d[G[0][i].to]=G[0][i].cost;
    }
    int num=0;

    for(int j=0;j<V;j++){
        int m=-1;
        for(int i=0;i<V;i++){
            if(used[i]==false && (m==-1 || d[m]>d[i])) m=i;
        }
        if (m==-1) break;
        used[m]=true;
        num+=d[m];
        for(int i=0;i<G[m].size();i++){
            d[G[m][i].to]=min(d[G[m][i].to],G[m][i].cost);
        }
    }
    return num;
}

int main(){
  int first;
  cin>>V>>E;
  for(int i=0;i<E;i++){
    int f,t;
    edge e;
    cin>>f>>e.to>>e.cost;
    G[f].push_back(e);
    t=e.to;
    e.to=f;
    G[t].push_back(e);
  }

  int fl = prim();
  cout << fl << endl;
}