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:
#!/usr/bin/env python3
# N,M = map(int,sys.stdin.readline().split())
# a = tuple(map(int,sys.stdin.readline().split())) # single line with multi param
# a = tuple(int(sys.stdin.readline()) for _ in range(N)) # multi line with single param
# a = tuple(tuple(map(int,sys.stdin.readline().rstrip().split())) for _ in range(N)) # multi line with multi param
# s = sys.stdin.readline().rstrip()
# N = int(sys.stdin.readline())
# INF = float("inf")

import sys,collections
sys.setrecursionlimit(10000)

INF = float("inf")

V,E = map(int,sys.stdin.readline().split())
stw = tuple(tuple(map(int,sys.stdin.readline().rstrip().split())) for _ in range(E)) # multi line with multi param

# n x n adjacency matrix
#G = [[-1,2,3],[2,-1,3],[1,2,-1]]
# G = [{} for _ in range(V)]
# for s,t,w in stw:
#     G[s][t] = w
#     G[t][s] = w
wst = [[w,s,t] for s,t,w in stw]
wst.sort()

parents = list(range(V))
def find(x):
  while parents[x] != x:
    x = parents[x]
    parents[x] = parents[parents[x]]
  return x

def union(s,t):
  sp = find(s)
  tp = find(t)
  if sp == tp:
    pass
  elif sp < tp:
    parents[sp] = tp
  else:
    parents[tp] = sp

INF = float("inf")
ret = 0
for w,s,t in wst:
    if find(s) != find(t):
        union(s,t)
        ret += w
print(ret)