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 <string>
#include <queue>
#include <vector>
#include <algorithm>
#include <utility>

#define INF 1000000000

using namespace std;

typedef long long int lli;
typedef pair<int, int> P;

struct edge{
	int to, cost;
};

int V, E;
vector<edge> e[10000];
int mincost[10000];
bool used[10000];


int main(void){
	cin >> V >> E;

	for(int i = 0;i < V;i++){
		mincost[i] = INF;
		used[i] = false;
	}

	for(int i = 0;i < E;i++){
		int a, b, c;
		cin >> a >> b >> c;
		edge d;
		d.to = b;
		d.cost = c;
		e[a].push_back(d);
		d.to = a;
		e[b].push_back(d);
	}


	mincost[0] = 0;
	long long int res = 0;

	while(true){
		int v = -1;
		for(int u = 0;u < V;u++){
			if(!used[u] && (v == -1 || mincost[u] < mincost[v])) v = u;
		}

		if(v == -1) break;
		used[v] = true;
		res += mincost[v];

		for(int u = 0;u < e[v].size();u++){
			mincost[e[v][u].to] = min(mincost[e[v][u].to], e[v][u].cost);
		}
	}
	cout << res << endl;
}