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())
ans = 0
par = [i for i in range(v)]
rank = [0]*v
def find(x,par):
    if par[x] == x:
        return par[x]
    else:
        return find(par[x],par)
def unite(x,y,par,rank):
    x = find(x,par)
    y = find(y,par)
    if rank[x] < rank[y]:
        par[x] = y
    else:
        par[y] = x
        if rank[x] == rank[y]:
            rank[x] += 1

L = []
for i in range(e):
    a,b,d = map(int,input().split())
    L.append([d,a,b])
L.sort()
for i in range(e):
    cur = heapq.heappop(L)
    if find(cur[1],par) != find(cur[2],par):
        ans += cur[0]
        unite(cur[1],cur[2],par,rank)
print(ans)