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 EDGE { int from, to, cost; };
bool operator < (const EDGE& a, const EDGE& b) {
	return a.cost < b.cost;
}

vector<EDGE> g;
int par[10000];

int find(int x)
{
	if (par[x] == x) return x;
	return par[x] = find(par[x]);
}

bool _union(int x, int y)
{
	x = find(x);
	y = find(y);
	if (x == y) return false;
	par[x] = y;
	return true;
}

int main()
{
	int V, E;
	scanf("%d %d", &V, &E);
	
	for (int i = 0; i < V; i++) par[i] = i;
	
	for (int i = 0; i < E; i++){
		int s, t, w;
		scanf("%d %d %d", &s, &t, &w);
		g.push_back((EDGE){s, t, w});
	}
	
	sort(g.begin(), g.end());
	
	int res = 0;
	for (int i = 0; i < g.size(); i++){
		EDGE &e = g[i];
		if (_union(e.from, e.to)) res += e.cost;
	}
	
	printf("%d\n", res);
	
	return 0;
}