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<stdio.h>
#include<stdlib.h>
#include<math.h>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<vector>
#include<list>
#include<map>
#include<set>
#include<string>

#include<stack>
#include<queue>
#include<climits>
#include<sstream>
using namespace std;
#define maxn 10005
struct Node{
    int x,y,val;
};
Node g[100010];
int n,m;
int F[maxn];
bool cmp(Node a,Node b){
    return a.val<b.val;
}
int find(int x){
    if(F[x]==-1) return x;
    return F[x]=find(F[x]);
}
int main(){

    int i,j,k;
    cin>>n>>m;
    for(i=0;i<m;i++)
        cin>>g[i].x>>g[i].y>>g[i].val;
    sort(g,g+m,cmp);


    memset(F,-1,sizeof F);
    int cnt=0,ans=0;
    for(i=0;i<m;i++){
        int fx=find(g[i].x);
        int fy=find(g[i].y);
        if(fx!=fy){
            F[fx]=fy;
            cnt++;
            ans+=g[i].val;
        }
        if(cnt==n-1) break;
    }
    cout<<ans<<endl;
    return 0;
}