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 PYTHON3):

Solution:
V, E = map(int, input().split())
inf = float('inf')
graphs = [list(map(int, input().split())) for _ in range(E)]
# コストが低い順に並べる
graphs.sort(key=lambda x: x[2])
# print(graphs)

nodes = [i for i in range(V)]
cost = 0


def root(node):
    if nodes[node] == node:
        return node
    nodes[node] = root(nodes[node])
    return nodes[node]


for i, j, k in graphs:
    if not root(i) == root(j):
        cost += k
        nodes[root(i)] = root(j)
print(cost)