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>
using namespace std;
typedef long long ll;
struct UF{
    vector<int>p,r;

    void makeSet (int x)
    {
        p.push_back(x);
        r.push_back(0);
    }
    int find(int x)
    {
        if(x==p[x])return x;
        return p[x]=find(p[x]);
    }
    void join(int x,int y)
    {
        x=find(x);
        y=find(y);
        if(x!=y)
        {
            if(r[x]>=r[y])
            {
                if(r[x]==r[y])
                    r[x]++;
                p[y]=x;
            }
            else p[x]=y;
        }
    }
};
int main()
{
    UF sd;
    int v,e,s,t,w,sum=0;
    vector<tuple<int,int,int> >c;
    cin>>v>>e;
    for(int i=0;i<v;i++)
    {
        sd.makeSet(i);
    }
    for(int i=0;i<e;i++)
    {
        cin>>s>>t>>w;
        c.push_back(make_tuple(w,s,t));
    }
    sort(c.begin(),c.end());
    for(int i=0;i<e;i++)
    {
        if(sd.find(get<1>(c[i]))!=sd.find(get<2>(c[i])))
        {
            sd.join(get<1>(c[i]),get<2>(c[i]));
            sum+=get<0>(c[i]);
        }
    }
    cout<<sum<<endl;
	return 0;
}