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 <queue>

using namespace std;

using ll = long long;

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

const ll MAX_V = 100010;

using P = pair<ll,ll>;

vector<P> G[MAX_V];
bool used[MAX_V];

ll V;

ll prim() {
  priority_queue<P,vector<P>,greater<P> > que;
  rep(i,V)used[i] = false;

  for(auto v : G[0]) {
    que.push(v);
  }

  used[0] = true;

  ll cou = 0;
  ll ret = 0;

  while(cou < V - 1 || !que.empty()) {
    P v = que.top();
    que.pop();

    if(!used[v.second]) {
      ret += v.first;
      used[v.second] = true;
      cou++;
      for(auto w : G[v.second]) {
        if(!used[w.second]) {
          que.push(w);
        }
      }
    }
  }
  return ret;
}

int main() {
  cin >> V;
  ll E;
  cin >> E;

  rep(i,E) {
    ll s,t,w;
    cin >> s >> t >> w;

    G[s].push_back(P(w,t));
    G[t].push_back(P(w,s));
  }

  cout << prim() << endl;
}