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<bits/stdc++.h>
#define F first
#define S second
using namespace std;
typedef long long ll;
typedef pair<ll,ll> P;
typedef pair<ll,P> PP;
ll n,m,a,b,c,ans,fa[10000],ra[10000];
vector<PP> v;
ll find(ll x){
    if(x==fa[x])return x;
    return fa[x]=find(fa[x]);
}
int uni(ll x,ll y){
    x=find(x),y=find(y);
    if(x==y)return 0;
    if(ra[x]<ra[y])swap(x,y);
    fa[y]=x;
    if(ra[x]==ra[y])ra[x]++;
    return 1;
}
int main(void){
    cin>>n>>m;
    for(int i=0;i<n;i++)fa[i]=i;
    for(int i=0;i<m;i++){
        cin>>a>>b>>c;
        v.push_back({c,{a,b}});
    }
    sort(v.begin(),v.end());
    for(PP x:v){
        if(find(x.S.F)!=find(x.S.S)){
            ans+=x.F;
            uni(x.S.F,x.S.S);
        }
    }
    cout<<ans<<endl;
}