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 <vector>
#include <queue>
#include <cstdint>
#include <tuple>

using namespace std;

struct E{
  int to;
  int_fast64_t cost;
};

vector<vector<E>>prim(vector<vector<E>>g){
  vector<vector<E>>res(g.size());
  using T=tuple<int_fast64_t,int,int>;
  using C=vector<T>;
  using Cmp=greater<T>;
  priority_queue<T,C,Cmp>q;
  q.push(T(0,0,-1));
  vector<bool>used(g.size(),false);
  while(!q.empty()){
    int_fast64_t cost=get<0>(q.top());
    int now=get<1>(q.top());
    int par=get<2>(q.top());
    q.pop();
    if(used[now])continue;
    used[now]=true;
    if(par!=-1)res[par].push_back({now,cost});
    for(auto e:g[now]){
      q.push(T(e.cost,e.to,now));
    }
  }
  return res;
}

#include <bits/stdc++.h>

int main(){
  int v,e;
  cin>>v>>e;
  vector<vector<E>>g(v);
  for(int i=0;i<e;i++){
    int s,t,w;
    cin>>s>>t>>w;
    g[s].push_back({t,w});
    g[t].push_back({s,w});
  }
  auto G=prim(g);
  int_fast64_t ans=0;
  for(int i=0;i<v;i++){
    for(auto it:G[i]){
      ans+=it.cost;
    }
  }
  cout<<ans<<endl;
}