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;
#define rep(i,n) for (ll i=0;i<(n);++i)
const ll MOD=1e9+7;

template<typename T>
struct Prim{
    using P=pair<T,int>;
    int n;
    vector<vector<pair<int,T>>> G;
    vector<bool> used;
    Prim(int n):n(n),G(n),used(n,false){}
    void add_edge(int u,int v,T c){
        G[u].emplace_back(v,c);
        G[v].emplace_back(u,c);
    }
    T build(){
        T res=0;
        priority_queue<P,vector<P>,greater<P>> pq;
        pq.emplace(0,0);
        while(!pq.empty()){
            P p=pq.top(); pq.pop();
            if (used[p.second]) continue;
            used[p.second]=true;
            res+=p.first;
            for (auto e:G[p.second]){
                pq.emplace(e.second,e.first);
            }
        }
        return res;
    }
};

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int V,E; cin >> V >> E;
    Prim<ll> P(V);
    rep(i,E){
        int s,t; ll w; cin >> s >> t >> w;
        P.add_edge(s,t,w);
    }
    cout << P.build() << endl;
}