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<bits/stdc++.h>

#define REP(i,s,n) for(int i=s;i<n;i++)
#define rep(i,n) REP(i,0,n)

using namespace std;

struct Edge{
  int to,cost;
  bool operator < (const Edge& e)const{
    return cost > e.cost;
  }
};

const int IINF = INT_MAX;

int V,E;
vector<Edge> G[10100];
int mincost[10100];
bool used[10100];

int main(){
  cin >> V >> E;
  rep(i,E){
    int s,t,w;
    cin >> s >> t >> w;
    G[s].push_back((Edge){t,w});
    G[t].push_back((Edge){s,w});
  }

  rep(i,V) mincost[i] = IINF, used[i] = false;
  mincost[0] = 0;

  priority_queue<Edge> Q;
  Q.push((Edge){0,0});
  int ans = 0;
  while(!Q.empty()){
    Edge e = Q.top(); Q.pop();
    if( used[e.to] ) continue;
    used[e.to] = true;
    ans += mincost[e.to];
    int cur = e.to;
    rep(i,G[cur].size()){
      int next = G[cur][i].to;
      if( used[next] ) continue;
      if( mincost[next] > G[cur][i].cost ){
        mincost[next] = G[cur][i].cost;
        Q.push((Edge){next,G[cur][i].cost});
      }
    }
  }

  cout << ans << endl;

  return 0;
}