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 <vector>
#include <queue>
#include <functional>
#include <string.h>

using namespace std;
static const int INF = 1e9;
static const int SIZE = 10001;
typedef pair<int, int> P;
struct edge
{
	int to;
	int cost;
};

bool isUsed[SIZE];
vector<edge> G[SIZE];

void solve()
{
	int V, E;
	cin >> V >> E;
	for (int i = 0; i < E; ++i)
	{
		int from, to, cost;
		cin >> from >> to >> cost;
		edge e1, e2;
		e1.to = to;
		e1.cost = cost;
		e2.to = from;
		e2.cost = cost;
		G[from].push_back(e1);
		G[to].push_back(e2);
	}
	memset(isUsed, 0, sizeof(isUsed));
	int ans = 0;
	priority_queue<P, vector<P>, greater<P> > pque;
	pque.push(P(0, 0));
	while (!pque.empty())
	{
		P p = pque.top();
		pque.pop();
		int v = p.second;
		if (isUsed[v])
		{
			continue;
		}
		isUsed[v] = true;
		ans += p.first;
		for (int i = 0; i < G[v].size(); ++i)
		{
			edge e = G[v][i];
			pque.push(P(e.cost, e.to));
		}
	}
	cout << ans << endl;
}

int main()
{
	solve();
	return(0);
}