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;
#define INF 1000000007
#define sf second.first
#define ss second.second
typedef pair<int,int> P;
typedef pair<int,P> iP;
int par[10000], leng[10000];
int find(int x){
	while(x != par[x]) x = par[x];
	return x;
}
int main(void){
	int v, e;
	cin >> v >> e;
	iP g[e];
	for(int i = 0; i < e; i++){
		int a, b, c;
		cin >> a >> b >> c;
		g[i] = iP(c, P(a, b));
	}
	sort(g, g + e);
	int ans = 0;
	for(int i = 0; i < v; i++) par[i] = i, leng[i] = 0;
	for(int i = 0; i < e; i++){
		iP d = g[i];
		if(find(d.sf) != find(d.ss)){
			ans += d.first;
			int x = find(d.sf), y = find(d.ss);
			if(leng[x] > leng[y]) par[y] = x;
			else if(leng[x] < leng[y]) par[x] = y;
			else par[y] = x, leng[x]++;
		}
	}
	cout << ans << endl;
	return 0;
}