There are N cards placed face down in a row. On each card, an integer 1 or 2 is written.

Let A_i be the integer written on the i-th card.

Your objective is to guess A_1, A_2, ..., A_N correctly.

You know the following facts:

* For each i = 1, 2, ..., M, the value A_{X_i} + A_{Y_i} + Z_i is an even number.



You are a magician and can use the following magic any number of times:

Magic: Choose one card and know the integer A_i written on it. The cost of using this magic is 1.

What is the minimum cost required to determine all of A_1, A_2, ..., A_N?

It is guaranteed that there is no contradiction in given input.

Constraints

* All values in input are integers.
* 2 \leq N \leq 10^5
* 1 \leq M \leq 10^5
* 1 \leq X_i < Y_i \leq N
* 1 \leq Z_i \leq 100
* The pairs (X_i, Y_i) are distinct.
* There is no contradiction in input. (That is, there exist integers A_1, A_2, ..., A_N that satisfy the conditions.)

Input

Input is given from Standard Input in the following format:


N M
X_1 Y_1 Z_1
X_2 Y_2 Z_2
\vdots
X_M Y_M Z_M


Output

Print the minimum total cost required to determine all of A_1, A_2, ..., A_N.

Examples

Input

3 1
1 2 1


Output

2


Input

6 5
1 2 1
2 3 2
1 3 3
4 5 4
5 6 5


Output

2


Input

100000 1
1 100000 100


Output

99999
import sys
range = xrange
input = sys.stdin.readline

class mergefind:
    def __init__(self,n):
        self.parent = list(range(n))
        self.size = [1]*n
        self.num_sets = n

    def find(self,a):
        to_update = []
       
        while a != self.parent[a]:
            to_update.append(a)
            a = self.parent[a]
       
        for b in to_update:
            self.parent[b] = a

        return self.parent[a]

    def merge(self,a,b):
        a = self.find(a)
        b = self.find(b)

        if a==b:
            return

        if self.size[a]<self.size[b]:
            a,b = b,a

        self.num_sets -= 1
        self.parent[b] = a
        self.size[a] += self.size[b]

    def set_size(self, a):
        return self.size[self.find(a)]

    def __len__(self):
        return self.num_sets

n,m = [int(x) for x in input().split()]

dsu = mergefind(n)
for _ in range(m):
    a,b,c = [int(x) for x in input().split()]
    dsu.merge(a-1,b-1)

print len(dsu)