Given a weighted undirected graph. Find the sum of weights of edges of a Minimum Spanning Tree.

Input:
Given 2 integers N and M. N represents the number of vertices in the graph. M represents the number of edges between any 2 vertices.
Then M lines follow, each line has 3 space separated integers $a_i$ , $b_i$, $w_i$ where $a_i$ and $b_i$ represents an edge from a vertex $a_i$ to a vertex $b_i$ and $w_i$ respresents the weight of that edge.

Output:
Print the summation of edges weights in the MST.

Constraints:
$2 \le N \le 10000$
$1 \le M \le 100000$
$1 \le a_i, b_i \le N$
$1 \le w_i \le 1000$