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 java.util.HashSet;
import java.util.Scanner;

public class Main 
{
	static int[] par;
	static int[] rank;
	
	static void union(int x, int y)
	{
		int rx = root(x);
		int ry = root(y);
		
		if(rank[rx] >= rank[ry])
		{
			par[ry] = rx;
			if(rank[rx] == rank[ry])
				rank[rx]++;
		}
		else par[rx] = ry;
	}
	
	static int root(int x)
	{
		if(par[x] != x)
			par[x] = root(par[x]);
		return par[x];
	}
	
	public static void main(String[] args) 
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		par = new int[n];
		rank = new int[n];
		int[] found = new int[n];
		for(int i = 0; i < n; i++)
			par[i] = i;
		
		for(int i = 0; i < m; i++)
		{
			int a = sc.nextInt()-1;
			int b = sc.nextInt()-1;
			int c = sc.nextInt();
			union(a,b);
		}
		
		int qt = 0;
		HashSet<Integer> set = new HashSet<>();
		for(int i = 0; i < n; i++)
		{
			set.add(root(i));
		}
		System.out.println(set.size());

	}

}
