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:
import heapq
V,E=map(int, input().split())
nodes = [[] for i in range(V)]
cost = [[] for i in range(V)]
for i in range(E):
    s,t,w = map(int, input().split())
    nodes[s].append(t)
    cost[s].append(w)
    nodes[t].append(s)
    cost[t].append(w)

visited = [False] * V
total = 0
h = [(0,-1,0)]
while h:
    c,s,t = heapq.heappop(h)
    if visited[t]:
        continue
    total += c
    visited[t] = True
    for i in range(len(nodes[t])):
        nv = nodes[t][i]
        if not visited[nv]:
            heapq.heappush(h,(cost[t][i],t,nv))
print(total)