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 <sstream>
#include <cstdio>
#include <stdlib.h>
#include <string>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;
#define MAX 10002
struct edge {
  int s,t,w;
};
int p[MAX];
int root(int x){
    if(p[x]==x)return x;
    return p[x] = root(p[x]);
}

priority_queue <edge, vector<edge>,greater<edge> > que;
bool operator > (const edge a,const edge b){return a.w>b.w;};

int main(){
  int v,e,s,t,w,rs,rt,res=0;
  edge tmp;
  cin>>v>>e;
  for(int i=1;i<v+1;i++)p[i]=i;
  for (int i=0;i<e;i++){
    cin>>tmp.s>>tmp.t>>tmp.w;
    que.push(tmp);
  }
  while(!que.empty()){
    s = que.top().s;
    t = que.top().t;
    w = que.top().w;
    que.pop();
    rs=root(s);
    rt=root(t);
    if(rs==rt)continue;
    p[rs] = rt;
    res += w;
  }
  cout<<res<<endl;
  return 0;
}