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.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Main {

	List<Integer>[] g;
	boolean[] seen;

	void dfs(int u) {
		seen[u] = true;
		for (int v : g[u]) {
			if (seen[v])
				continue;
			dfs(v);
		}
	}

	void solve(Scanner in, PrintWriter out) {
		int n = in.nextInt(), m = in.nextInt();
		g = new ArrayList[n + 1];
		seen = new boolean[n + 1];
		for (int i = 0; i <= n; ++i) {
			g[i] = new ArrayList<>();
		}
		for (int i = 0; i < m; ++i) {
			int u = in.nextInt(), v = in.nextInt(), c = in.nextInt();
			g[u].add(v);
			g[v].add(u);
		}
		int ans = 0;
		for (int i = 1; i <= n; ++i) {
			if (!seen[i]) {
				dfs(i);
				++ans;
			}
		}
		out.println(ans);
	}

	public static void main(String[] args) {
		try (Scanner in = new Scanner(System.in); PrintWriter out = new PrintWriter(System.out)) {
			new Main().solve(in, out);
		}
	}
}
