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 <iostream>
#include <fstream>
#include <queue>
#include <cmath>
#include <math.h>
#include <algorithm>
#include <vector>

using namespace std;

ifstream in("mst.in");

int v, e;
vector<pair<int, pair<int, int> > > g;
int parent[10005];

int find_parent(int r){
	if(parent[r] == r)return r;
	return parent[r] = find_parent(parent[r]);
}

int Kruskal(){
	for(int i = 0; i < v; ++i)
		parent[i] = i;

	sort(g.begin(), g.end());

	int cnt = 0, cost = 0;

	for(int i = 0; i < g.size(); i++){

		int u = find_parent(g[i].second.first);
		int	n = find_parent(g[i].second.second);
		int	w = g[i].first;

		if(u != n){
			parent[u] = n;
			cost += w;
			cnt++;
		}

		if(cnt == v-1) 
			break;
	}

	return cost;
}

int main(){
	cin >> v >> e;
	for(int i = 0; i < e; ++i){
		int x, y, c;
		cin >> x >> y >> c;
		g.push_back(make_pair(c, make_pair(x,y)));
	}

	cout << Kruskal() << '\n';

	return 0;
}