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 rep(i,n) for(int (i)=0;(i)<(n);(i)++)
using namespace std;

const int vmax=10010;
const int inf=1023456789;

int N,M;
typedef tuple<int,int,int> node;
vector<node> graph;

int par[vmax];
void init(){rep(i,vmax) par[i]=i;}
int find(int x){return (par[x]==x)?x:par[x]=find(par[x]);}
void unite(int a,int b){a=find(a),b=find(b);par[a]=b;}
bool same(int a,int b){return find(a)==find(b);}

int kruskal(){
	init();
	sort(begin(graph),end(graph));
	int res=0;
	for(auto &e:graph){
		int a,b,c;
		tie(c,a,b)=e;
		if(!same(a,b)) unite(a,b),res+=c;
	}
	return res;
}

int main(void){
	cin >> N >> M;
	rep(i,M){
		int a,b,c;
		cin >> a >> b >> c;
		graph.push_back(node(c,a,b));
	}
	cout << kruskal() << endl;
	return 0;
}