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<functional>
#include<algorithm>
#define MM 2000000000
#define F first
#define S1 second.first
#define S2 second.second
using namespace std;
typedef pair<int,int> P;
typedef pair<int,P> P2;
P2 pp[200000];
int main(void)
{
	int v,e,i,j,s,t,w,par[100000],leng[100000],sum,x,y,cnt;
	scanf("%d %d",&v,&e);
	for(i=0;i<v;i++)	{
		par[i]=i;	leng[i]=1;
	}
	for(i=0;i<e;i++)	{
		scanf("%d %d %d",&s,&t,&w);
		pp[i].F=w;	pp[i].S1=s;	pp[i].S2=t;
	}
	sort(pp,pp+e);
	sum=0;	cnt=0;
	for(i=0;i<e;i++)	{
		x=pp[i].S1;	y=pp[i].S2;
		while(x!=par[x])	x=par[x];
		while(y!=par[y])	y=par[y];
		if(x!=y)	{
			sum+=pp[i].F;
			cnt++;
			if(leng[x]>leng[y])	par[y]=x;
			else if(leng[x]<leng[y])	par[x]=y;
			else {
				par[y]=x;
				leng[x]++;
			}
		}
		if(cnt==v-1)	break;
	}
	printf("%d\n",sum);
	return 0;
}