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 <cstdio>
#include <queue> 
using namespace std;
const int MAXV = 1e4 + 7;
struct edge {
	int u, v, w;
	edge(int u, int v, int w) :u(u), v(v), w(w) {}
	bool operator < (const edge& rhs) const {
		return w > rhs.w;
	}
};
int p[MAXV];
priority_queue<edge> q;
int find(int x) {
	return p[x] == x ? x : (p[x] = find(p[x]));
}
int main() {
    int v, e, ans = 0;
    scanf("%d%d", &v, &e);
    for (int i = 0; i < v; i++) {
    	p[i] = i;
	}
	for (int i = 0; i < e; i++) {
		int s, t, w;
		scanf("%d%d%d", &s, &t, &w);
		q.push(edge(s, t, w));
	}
	while (!q.empty()) {
		edge cur = q.top();
		q.pop();
		int p1 = find(cur.u), p2 = find(cur.v);
		if (p1 != p2) {
			p[p2] = p1;
			ans += cur.w;
		}
	}
    printf("%d\n", ans);
	return 0;
}