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 <algorithm>
#include <vector>
#include <queue>
 
using namespace std;
 
struct edge { int to, cost; };
typedef pair<int, int> P;
 
const int MAX_V = 10000;
const int INF = 1 << 28;
 
int V;
vector<edge> G[MAX_V];
int d[MAX_V];
bool vis[MAX_V];
 
int prim(){
	int res = 0;
	priority_queue<P, vector<P>, greater<P> > que;
	fill(d, d + V, INF);
	fill(vis, vis + V, false);
	d[0] = 0;
	que.push(P(0, 0));
	while(!que.empty()){
		P p = que.top(); que.pop();
		int v = p.second;
		if(vis[v]) continue;
		vis[v] = true;
		res += p.first;
		for(int i=0;i<G[v].size();i++){
			edge e = G[v][i];
			if(d[e.to] > e.cost){
				d[e.to] = e.cost;
				que.push(P(d[e.to], e.to));
			}
		}
	}
	return res;
}
 
int main(){
	int E;
	cin >> V >> E;
	for(int i=0;i<E;i++){
		int s, t, w;
		cin >> s >> t >> w;
		G[s].push_back((edge){t, w});
		G[t].push_back((edge){s, w});
	}
	cout << prim() << endl;
	return 0;
}