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
from collections import defaultdict

INF = float('inf')


V, E = map(int, input().split())
Adj_list = defaultdict(set)

for i in range(E):
    s, t, w = map(int, input().split())
    Adj_list[s].add((t, w))
    Adj_list[t].add((s, w))
    
def prim(x):
    d = [INF] * x
    d[0] = 0
    isVisited = [False] * x
    hq = [(0,0)] 
    
    while hq:
        u = heapq.heappop(hq)[1]
        isVisited[u] = True
        
        for v, c in Adj_list[u]:
            if not isVisited[v] and d[v] > c:
                d[v] = c
                heapq.heappush(hq, (c, v))
    return sum(d)

print(prim(V))