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>
#define INF 1000000000
#define MAX_V 10000
#define MAX_E 100000
using namespace std;
typedef pair<int, int> P;
struct edge { int u, v, cost; };

bool comp(const edge& e1, const edge& e2){
	return e1.cost < e2.cost;
}

int V, E;
edge es[MAX_E];

class UnionFind {
	vector<int> data;
	int root(int a) {
		return data[a] < 0 ? a : data[a] = root(data[a]);
	}
public:
	UnionFind(int n) : data(n, -1) {}
	bool Find(int a, int b) {
		return root(a) == root(b);
	}
	void Union(int a, int b) {
		int ra = root(a), rb = root(b);
		if (ra == rb) return;
		if (data[ra] < data[rb]) {
			data[ra] += data[rb];
			data[rb] = a;
		}
		else {
			data[rb] += data[ra];
			data[ra] = b;
		}
	}
};

int Kruskal() {
	int res = 0;
	UnionFind uf(V);
	sort(es, es + E, comp);
	for (int i = 0; i < E; i++) {
		edge e = es[i];
		if (!uf.Find(e.u, e.v)) {
			uf.Union(e.u, e.v);
			res += e.cost;
		}
	}
	return res;
}

int main()
{
	cin >> V >> E;
	for (int i = 0; i < E; i++) {
		cin >> es[i].u >> es[i].v >> es[i].cost;
	}
	cout << Kruskal() << endl;
	return 0;
}