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;

int n,m;
const int MAXN = 10010;

struct edg{
    int u,v,cost;
};

int p[MAXN],sz[MAXN];
vector<edg> edgs;

bool cmp(edg a,edg b){
    return a.cost<b.cost;
}

int find(int x){
    return (x==p[x]) ? x : p[x]=find(p[x]);
}
bool unite(int a,int b){
    a = find(a);
    b = find(b);
    if(a==b){
        return false; //already same cc
    }
    if(sz[b] > sz[a]){ swap(a,b);}
    sz[a]+=sz[b];
    p[b] = a;
    return true;
}

void kruskal()
{
    for(int i=0; i<n; i++){
        p[i]=i; sz[i]=1;
    }
    sort(edgs.begin(),edgs.end(),cmp);
    int ans = 0;
    for(auto e : edgs){
        if( unite(e.u,e.v)){
            ans+=e.cost;
        }
    }
    cout<<ans<<"\n";
}
int main() {
    // freopen("./input.txt","r",stdin);
    // freopen("./output.txt","w",stdout);
    cin>>n>>m;
    for(int i=0; i<m; i++){
        int a,b,c; cin>>a>>b>>c;
        edgs.push_back({a,b,c});
    }
    kruskal();
}