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.io.InputStream;
import java.io.PrintStream;
import java.util.Arrays;
import java.util.Scanner;

class UnionFind {

	int[] par;

	public UnionFind(int size) {
		par = new int[size];
		Arrays.fill(par, -1);
	}

	public int root(int x) {
		if (par[x] < 0) {
			return x;
		}
		int z = root(par[x]);
		par[x] = z;
		return z;
	}

	public boolean same(int a, int b) {
		return root(a) == root(b);
	}

	public void unite(int a, int b) {
		if (!same(a, b)) {
			int ra = root(a);
			int rb = root(b);

			if (par[ra] < par[rb]) {
				par[ra] += par[rb];
				par[rb] = ra;
			} else {
				par[rb] += par[ra];
				par[ra] = rb;
			}
		}
	}

	public int size(int a) {
		return -par[root(a)];
	}

}

public class Main {
	InputStream in = System.in;
	PrintStream out = System.out;

	public void _main(String[] args) {
		Scanner sc = new Scanner(in);

		int N = sc.nextInt();
		int M = sc.nextInt();

		UnionFind uf = new UnionFind(N);

		for (int i = 0; i < M; i++) {
			uf.unite(sc.nextInt() - 1, sc.nextInt() - 1);
			sc.nextInt();
		}

		int ans = 0;
		for (int i = 0; i < N; i++) {
			if (uf.par[i] < 0)
				ans++;
		}
		out.println(ans);

		sc.close();

	}

	public static void main(String[] args) {
		new Main()._main(args);
	}

}
