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;

#define fi first
#define se second
#define pb push_back

typedef long long LL;
typedef long double LD;

const LL INF = (1LL << 60);

typedef pair<LL,int> PL;
LL prim(vector<PL> adjList[], int n);

int main() {

  ios_base::sync_with_stdio(0); cin.tie(0);

  vector<PL> adjList[10005];

  int n, m;
  cin >> n >> m;

  for (int i = 0; i < m; i++) {
    int s, t; LL w;
    cin >> s >> t >> w;

    adjList[s].push_back({w, t});
    adjList[t].push_back({w, s});
  }

  LL res = prim(adjList, n);

  cout << res << endl;

  return 0;
}

/**
 *
 * tested on http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=GRL_2_A
 */
LL prim(vector<PL> adjList[], int n) {
  LL ans = 0;

  vector<bool> visited; visited.assign(n, false);
  priority_queue<PL,vector<PL>,greater<PL>> pq; 

  pq.push({0, 0});
  while (!pq.empty()) {
    int u; LL w;
    tie(w, u) = pq.top(); pq.pop();
    
    if (visited[u])
      continue;

    visited[u] = true;
    ans += w;
    
    for (PL v : adjList[u]) {
      pq.push(v);
    }
  }

  return ans;
}