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>
using namespace std;
using ll = long long;

class edge {
public:
  int to, cost;
  edge(int a, int b) {to = a, cost = b;}; 
};

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);

  ll V, E; cin >> V >> E;
  vector<edge> G[V];
  for (ll i = 0; i < E; i++) {
    ll s, t, w; cin >> s >> t >> w;
    G[s].emplace_back(edge(t, w));
    G[t].emplace_back(edge(s, w));
  }

  ll ans = 0;
  vector<bool> used(V);
  priority_queue<pair<ll, ll>, vector<pair<ll, ll>>, greater<pair<ll, ll>>> q;
  q.push(make_pair(0, 0));

  while (!q.empty()) {
    pair<ll, ll> p = q.top(); q.pop();
    if (used[p.second]) continue;
    used[p.second] = true;
    ans += p.first;

    for (auto n: G[p.second]) {
      if (used[n.to]) continue;
      q.push(make_pair(n.cost, n.to));
    }
  }

  cout << ans << '\n';

  return 0;
}