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<cstdio>
#include<vector>
#include<queue>
#include<algorithm>
using namespace std;

//Prim
struct edge{int to,cost;};

int main(){
  int V,E;
  vector<edge> G[10000];
  scanf("%d %d",&V,&E);
  for(int i=0;i<E;i++){
    int s,t,w;
    scanf("%d %d %d",&s,&t,&w);
    edge tmp;
    tmp.cost = w;
    tmp.to = t;
    G[s].push_back(tmp);
    tmp.to = s;
    G[t].push_back(tmp);
  }
  int ans = 0;
  bool used[V];
  fill(used,used+V,false);
  priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > q;
  q.push(make_pair(0,0));
  while(!q.empty()){
    pair<int,int> p = q.top();
    q.pop();
    int c = p.first;
    int v = p.second;
    if(used[v]) continue;
    used[v] = true;
    ans+=c;
    for(int i=0;i<G[v].size();i++){
      q.push(make_pair(G[v][i].cost,G[v][i].to));
    }
  }
  printf("%d\n",ans);
  return 0;
}