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( ))

Edg = []

for _ in range(e):
    s,t,w = map(int, input().split( ))
    Edg.append([w,s,t])
    Edg.append([w,t,s])
    
Edg.sort(reverse = True)

UF = [i for i in range(v)]

ans = 0
#cnt = v

for i in range(2*e):#無向辺で2倍
    edg = Edg.pop()
    s, t = edg[1],edg[2]
    Ls = [s]
    Lt = [t]
    root_s = UF[s]
    
    while root_s!=s:
        Ls.append(root_s)
        s = root_s
        root_s = UF[root_s]
        
    root_t = UF[t]
    while root_t!=t:
        Lt.append(root_t)
        t = root_t
        root_t = UF[root_t]
    
    if root_s == root_t:
        continue
    
    else:
        #print(root_t,root_s)
        for j in Lt:
            UF[j] = root_s
        #print(edg)
        ans += edg[0]
        #cnt -= 1
    #print(*UF)


print(ans)