Problem8602--GRL_2_A : Minimum Spanning Tree

8602: GRL_2_A : Minimum Spanning Tree

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Time Limit : 1.000 sec  Memory Limit : 256 MiB

Description

Find the sum of weights of edges of the Minimum Spanning Tree for a given weighted undirected graph G = (V, E).

Input

In the first line, two integers $|V|$ 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.

In the following $|E|$ lines, three integers $s_i$ and $t_i$ represent source and target verticess of $i$-th edge (undirected) and $w_i$ represents the weight of the $i$-th edge.

Output

Print the sum of the weights of the Minimum Spanning Tree.

Constraints

$1 ≤ |V| ≤ 10,000$
$0 ≤ |E| ≤ 100,000$
$0 ≤ w_i ≤ 10,000$
The graph is connected
There are no parallel edges
There are no self-loops

Sample 1 Input

4 6
0 1 2
1 2 1
2 3 1
3 0 1
0 2 3
1 3 5

Sample 1 Output

3

Sample 2 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

Sample 2 Output

5

HINT

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