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>
#include<utility>

#define VMAX 10000
using namespace std;
typedef pair<long long, pair<int, int>> pli;
vector<pli> edge[VMAX];
int color[VMAX];

long long Prim(int n, int s){
    priority_queue<pli, vector<pli>, greater<pli>> q;
    for(int i=0; i<n; ++i){
        color[i] = 0;
    }
    for(int i=0; i<edge[s].size(); ++i){
        q.push(edge[s][i]);
    }
    color[s] = 1;
    int u, v, w;
    long long res = 0;
    while(!q.empty()){
        w = q.top().first;
        v = q.top().second.first;
        u = q.top().second.second;
        q.pop();
        if(!color[v]){
            color[v] = 1;
            res += w;
            for(int i=0; i<edge[v].size(); ++i){
                q.push(edge[v][i]);
            }
        }
    }
    return res;
}

int main(){
    int v, e, w, s, t;
    cin>>v>>e;
    for(int i=0; i<e; ++i){
        cin>>s>>t>>w;
        edge[s].push_back(make_pair(w, make_pair(t, s)));
        edge[t].push_back(make_pair(w, make_pair(s, t)));
    }

    long long res = Prim(v, 0);
    cout<<res<<endl;

    return 0;
}