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 UnionFind {
    vector<int> par;
    UnionFind(int N):par(N) {
        for (int i=0; i<N; i++) par[i]=i;
    }
    int root (int x) {
        if (par[x]==x) return x;
        return par[x]=root(par[x]);
    }
    void unite(int x,int y) {
        int rx=root(x);
        int ry=root(y);
        if (rx==ry) return;
        par[rx]=ry;
    }
    bool same (int x,int y) {
        int rx=root(x);
        int ry=root(y);
        return rx==ry;
    }
};

int main() {
   int V,E;
   cin >> V >> E;
   priority_queue<tuple<int,int,int>,vector<tuple<int,int,int>>,greater<tuple<int,int,int>>> G;
   for (int i=0; i<E; i++) {
       int s,t,w;
       cin >> s >> t >> w;
       G.push(make_tuple(w,s,t));
   }
   UnionFind tree(V);
   int count=0;
   for (int i=0; i<E; i++) {
       tuple<int,int,int> a=G.top();
       G.pop();
       if (tree.same(get<1>(a),get<2>(a))) continue;
       tree.unite(get<1>(a),get<2>(a));
       count+=get<0>(a);
   }
   cout << count << endl;
}