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;

const int MXN = 1e4+5;
vector<pair<int, pair<int, int>>> es;

int parent[MXN];
int size[MXN];

void init_uf() {
    for (int i=0; i<MXN; i++) {
        parent[i] = i;
        size[i] = 1;
    }
}

int fs(int v) {
    if (v == parent[v])
        return v;
    return parent[v] = fs(parent[v]);
}

void us(int a, int b) {
    a = fs(a);
    b = fs(b);
    if (a != b) {
        if (size[a] < size[b])
            swap(a, b);
        parent[b] = a;
        size[a] += size[b];
    }
}

long long kruskal() {
    init_uf();
    sort(es.begin(), es.end());
    long long w = 0;
    for (auto e: es) {
        if (fs(e.second.first) == fs(e.second.second)) continue;
        w += e.first;
        us(e.second.first, e.second.second);
    }
    return w;
}

int main() {
    
    int n, m;
    cin >> n >> m;
    while (m--) {
        int v, u, w;
        cin >> v >> u >> w;
        es.push_back({w, {v, u}});
    }
    
    cout << kruskal() << endl;
}