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 PYTHON):

Solution:
from collections import defaultdict
V, E = map(int, raw_input().split())
ans = 0
parent = [i for i in range(V)]
v = defaultdict(set)
for i in range(V):
    v[i].add(i)
edges = [map(int, raw_input().split()) for i in range(E)]
edges.sort(key = lambda x:x[2])
cnt = 0
while edges:
    if cnt == V - 1: break
    s, t, d = edges.pop(0)
    a, b = parent[s], parent[t]
    if a != b:
        if a > b: a, b = b, a
        v[a] = v[a] | v[b]
        for i in v[b]: parent[i] = a
        ans += d
        cnt += 1
print ans