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;
typedef long long ll;
typedef pair<ll,ll> pll;

int main() {
  ll v,e;
  cin >> v >> e;
  vector<map<ll,ll>> E(v);
  for(ll i=0;i<e;i++) {
    ll s,t,dis;
    cin >> s >> t >> dis;
    E[s][t]=dis;
    E[t][s]=dis;
  }
  set<ll> al;
  al.insert(0);
  priority_queue<pll,vector<pll>,greater<pll>> q;
  for(auto p:E[0]) {
    q.push(pll(p.second,p.first));
  }
  ll ans=0;
  while(al.size()<v) {
    auto p=q.top();
    q.pop();
    if(al.count(p.second)) continue;
    ans+=p.first;
    al.insert(p.second);
    for(auto pp:E[p.second]) {
      q.push(pll(pp.second,pp.first));
    }
  }
  cout << ans << endl;
}