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 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		StringBuilder sb = new StringBuilder();
		int n = sc.nextInt();
		int m = sc.nextInt();
		Union union = new Union(n);
		int x, y, z;
		for (int i = 0; i < m; i++) {
			x = sc.nextInt() - 1;
			y = sc.nextInt() - 1;
			z = sc.nextInt();
			union.unite(x, y);
		}
		HashSet<Integer> hs = new HashSet<>();
		for (int i = 0; i < n; i++) {
			hs.add(union.getparent(i));
		}
		System.out.println(hs.size());
	}
}

class Union {

	private int[] rank;
	private int[] parent;

	public Union(int n) {
		rank = new int[n];
		parent = new int[n];
		for (int i = 0; i < n; i++) {
			parent[i] = i;
		}
	}

	public int root(int n) {
		if (n == parent[n]) {
			return n;
		}
		return parent[n] = root(parent[n]);
	}

	public void unite(int a, int b) {
		int aroot = root(a);
		int broot = root(b);
		if (aroot == broot) {
			return;
		}
		if (rank[aroot] > rank[broot]) {
			parent[broot] = aroot;
		} else if (rank[aroot] < rank[broot]) {
			parent[aroot] = broot;
		} else if (rank[aroot] == rank[broot]) {
			parent[broot] = aroot;
			rank[aroot]++;
		}
	}

	public int getparent(int n) {
		return parent[n] = root(parent[n]);
	}
}