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<stdio.h>
#include<algorithm>
#include<queue>
using namespace std;

const int V_MAX = 10000;
const int INF = 100000000;

struct Edge {
	bool operator< (const Edge& e)const {
		return e.w > w;
	}
	int s;
	int t;
	int w;
};

int parent(int uft[], int child) {
	if (uft[child] == -1)return child;
	return uft[child] = parent(uft, uft[child]);
}

int main() {
	int v, e;
	vector<Edge> edge;
	int uft[V_MAX];
	int ans = 0;
	
	scanf("%d%d", &v, &e);
	for (int i = 0; i < v; i++) {
		uft[i] = -1;
	}
	for (int i = 0; i < e; i++) {
		Edge e;
		scanf("%d%d%d", &e.s, &e.t, &e.w);
		
		edge.push_back(e);
	}

	sort(edge.begin(), edge.end());

	for (int i = 0; i < e; i++) {
		Edge e = edge[i];
		
		int p1 = parent(uft, e.s);
		int p2 = parent(uft, e.t);
		if (p1 != p2) {
			uft[p1] = p2;
			ans += e.w;
		}
	}

	printf("%d\n", ans);

	return 0;
}