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 <cstdio>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
using namespace std;
#define pb        emplace_back
#define fi        first
#define se        second
#define outl(x)   cout << (x) << '\n'
#define rep(i,n)     for(int i=0; i<(n); ++i)
typedef pair<int,int> pii;

int V, E;
vector<pii> G[100010];

int prim()
{
    vector<bool> used(V+1, false);
    priority_queue< pii, vector<pii>, greater<pii> > pq;
    int sum = 0;
    pq.emplace(pii(0,0));

    while ( !pq.empty() ) {
        const auto now = pq.top(); pq.pop();
        if (used[now.se]) continue;

        sum += now.fi;
        used[now.se] = true;
        for (const auto &e : G[now.se]) {
            pq.emplace(e);
        }
    }
    return sum;
}

signed main()
{
    cin.tie(0), ios::sync_with_stdio(false);

    cin >> V >> E;
    rep(i, E) {
        int s, t, w;
        cin >> s >> t >> w;
        G[s].pb(pii(w, t));
        G[t].pb(pii(w, s));
    }

    outl(prim());
}