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 <cmath>
#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
using namespace std;
const int MAXN = 200010 ;
struct tjz
{
	int u, v, w;
}edge[MAXN];
int n, m;
bool cmp(tjz x, tjz y)
{
	return x.w < y.w;
}
int f[MAXN], ans;
int getfa(int x)
{
	if (f[x] == x) return x;
	return f[x] = getfa(f[x]);
}
int main()
{
	cin >> n >> m;
	for (int i = 1; i <= m; ++i) cin >> edge[i].u >> edge[i].v >> edge[i].w ;
	sort(edge + 1, edge + m + 1, cmp);
	for (int i = 1; i <= n; ++i) f[i] = i;
	for (int i = 1; i <= m; ++i)
	{
		int fa1 = getfa(edge[i].u);
		int fa2 = getfa(edge[i].v);
		if (fa1 != fa2)
		{
			f[fa1] = fa2;
			ans += edge[i].w;
		}
	}
	cout << ans << endl;
	return 0;
}