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 <cstdio>
#include <algorithm>
using namespace std;

const int maxn = 200000 + 5;

struct node {
	int x;
	int y;
	int v;
}r[maxn];

int n,m;
int f[maxn];

bool cmp(node a,node b){
	return a.v < b.v;
}

int find(int x){
	if(f[x] == x)return x;
	else return f[x] = find(f[x]);
}

int Kruskal(){
	int ans = 0;
	for(int i = 1;i <= n; i++)f[i] = i;
	sort(r+1,r+m+1,cmp);
	for(int i = 1;i <= m; i++){
		int x = find(r[i].x),y = find(r[i].y);
		if(x != y){
			ans += r[i].v;
			f[x] = y;
		}
	}
	return ans;
}

int main(){
	scanf("%d%d",&n,&m);
	for(int i = 1;i <= m; i++)scanf("%d%d%d",&r[i].x,&r[i].y,&r[i].v);
	int ans = Kruskal();
	printf("%d\n",ans);
}