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<vector>
#include<queue>
using namespace std;

struct UF{
    vector<int> p;
    int n;

    UF(int siz){
        n = siz;
        p.resize(n);
        for(int i = 0; i < n; i++)  p[i] = i;
    }

    int findSet(int x){
        if(p[x] != x)   p[x] = findSet(p[x]);
        return p[x];
    }

    bool same(int x, int y){
        return findSet(x) == findSet(y);
    }

    void unite(int x, int y){
        x = findSet(x), y = findSet(y);
        p[x] = y;
    }
};

int main(){
    int v, e;
    cin >> v >> e;
    UF uf(v);
    priority_queue<pair<int,pair<int,int>>> q;
    while(e-- > 0){
        int s, t, w;
        cin >> s >> t >> w;
        q.push({-w, {s, t}});
    }
    int ans = 0;
    while(!q.empty()){
        auto p = q.top();   q.pop();
        int i = p.second.first, j = p.second.second;
        if(uf.same(i,j))    continue;
        uf.unite(i,j);
        ans -= p.first;
    }
    cout << ans << endl;
    return 0;
}