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;

struct edge { int from, to, cost; };

bool comp(const edge &e1, const edge &e2) {
  return e1.cost < e2.cost;
}

typedef pair<long long, int> plli;

int parent[10000];
int rnk[10000];
void init(int n) {
  for (int i=0; i<n; i++) {
    parent[i] = i;
    rnk[i] = 0;
  }
}

int find(int i) {
  if (parent[i] == i) {
    return i;
  }
  return parent[i] = find(parent[i]);
}
void unite(int i, int j) {
  i = find(i);
  j = find(j);
  if (rnk[i] < rnk[j]) {
    parent[i] = j;
  } else {
    parent[j] = i;
    if (rnk[i] == rnk[j]) {
      ++rnk[i];
    }
  }
}
int main() {
  int n, m;
  cin>>n>>m;
  vector<edge> edges;
  for (int i=0; i<m; i++) {
    int s, t, d;
    cin>>s>>t>>d;
    edges.push_back({s, t, d});
  }
  init(n);
  sort(edges.begin(), edges.end(), comp);

  long long sum= 0;
  for (auto e: edges) {
    if (find(e.from) == find(e.to)) {
      continue;
    }
    sum += e.cost;
    unite(e.from, e.to);
  }
  cout<<sum<<endl;
}