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:
from heapq import heappop, heappush
v, e = map(int, input().split())
G = [[] for _ in range(v)]
for _ in range(e):
    s, t, w = map(int, input().split())
    G[s].append((w,t))
    G[t].append((w,s))
been = [0]*v
ans = 0
# print(G)
queue = []
a = (0,0)
heappush(queue,a)
been[0] = 1
# print(heappop(queue))
while sum(been) != v:
    while len(queue):
        a = heappop(queue)
        if been[a[1]] == 0:
            been[a[1]] = 1
            break
    
    ans += a[0]
    # print(been,a,ans,queue)
    for nex in G[a[1]]:
        heappush(queue, (nex[0], nex[1]))
print(ans)