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=1000010;
const int inf=1023456789;

int N,M;
struct node{int to,cost;};
vector<node> graph[vmax];

typedef tuple<int,int> state;
int dist[vmax];
bool used[vmax];

int prim(){
	rep(i,N)dist[i]=inf,used[i]=false;
	dist[0]=0;
	int res=0;
	priority_queue<state,vector<state>,greater<state>> q;
	q.push(state(0,0));
	while(!q.empty()){
		int c,v;tie(c,v)=q.top();q.pop();
		if(used[v]) continue;
		res+=dist[v];
		used[v]=true;
		for(auto &e:graph[v]){
			int nc=e.cost;
			int nv=e.to;
			if(used[nv]) continue;
			if(dist[nv]>nc){
				dist[nv]=nc;
				q.push(state(nc,nv));
			}
		}
	}
	return res;
}

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