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())
data = []
for i in range(e):
    data.append(list(map(int, input().split())))

from collections import deque

q = deque(sorted(data, key=lambda x: x[2]))


parent = [i for i in range(v)]
rank = [0 for i in range(v)]

# Union-Find  ---------------
def find(x):
    if parent[x] == x:
        return x
    else:
        parent[x] = find(parent[x])
        return parent[x]

def judge(a, b):
    a_parent = find(a)
    b_parent = find(b)
    if a_parent == b_parent:
        return True
    else:
        return False

def merge(a, b):
    a_parent = find(a)
    b_parent = find(b)
    if a_parent == b_parent:
        return
    else:
        if rank[a_parent] > rank[b_parent]:
            parent[b_parent] = a_parent
        elif rank[a_parent] < rank[b_parent]:
            parent[a_parent] = b_parent
        else:
            parent[a_parent] = b_parent
            rank[b_parent] += 1

#----------------------------


ans = 0
while len(q) > 0:
    a = q.popleft()
    if not judge(a[0], a[1]):
        merge(a[0], a[1])
        ans += a[2]

print(ans)