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<algorithm>
#include<vector>
using namespace std;

static const int MAX = 10000;

int n;

class Edge {
public:
	int s, t, w;
	Edge() {}
	Edge(int s, int t, int w): s(s), t(t), w(w) {}

	bool operator < (const Edge &e) const{
		return w < e.w;
	}
};

vector<Edge> E;
int p[MAX];

int ans() {
	for (int i = 0; i < n; i++)	{
		p[i] = i;
	}
	int cnt = 0, sum = 0, i = 0;
	sort(E.begin(), E.end());

	while (cnt < n - 1) {
		int s1 = E[i].s, t1 = E[i].t;
		while (p[s1] != s1) s1 = p[s1];
		while (p[t1] != t1) t1 = p[t1];
		if (s1 != t1) {
			p[s1] = t1;
			sum += E[i].w;
			cnt++;
		}
		i++;
	}
	return sum;
}

int main() {
	int e;
	cin >> n >> e;
	int s, t, w;
	for (int i = 0; i < e; i++) {
		cin >> s >> t >> w;
		E.push_back(Edge(s, t, w));
	}

	cout << ans() << endl;

	return 0;
}