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.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.util.*;

public class Main {
	int N, M;
	Set<Integer>[] conns;
	boolean[] done;
	int result;

	Main(int N, int M, List<String> lines) {
		this.N = N;
		this.M = M;
		this.conns = new Set[N];
		this.done = new boolean[N];
		Arrays.fill(this.done, false);
		for (int i = 0; i < N; ++i) {
			this.conns[i] = new HashSet<>();
		}
		for (String line : lines) {
			String[] tokens = line.split(" ");
			int X = Integer.parseInt(tokens[0]);
			int Y = Integer.parseInt(tokens[1]);
			int Z = Integer.parseInt(tokens[2]);
			this.conns[X - 1].add(Y - 1);
			this.conns[Y - 1].add(X - 1);
		}
		result = calc2();
	}

	int calc2() {
		int result = 0;
		for (int i = 0; i < N; ++i) {
			if (!this.done[i]) {
				++result;
				this.calc(i);
			}
		}
		return result;
	}

	void calc(int nodeIndex) {
		this.done[nodeIndex] = true;
		for (Integer key : conns[nodeIndex]) {
			this.conns[key].remove(nodeIndex);
		}
		for(Integer key: conns[nodeIndex]) {
			calc(key);
		}
		this.conns[nodeIndex].clear();
	}

	public static void main(String[] args) throws IOException {
		InputStreamReader reader = new InputStreamReader(System.in, StandardCharsets.UTF_8);
		BufferedReader in = new BufferedReader(reader);
		String[] tokens = in.readLine().split(" ");
		int N = Integer.parseInt(tokens[0]);
		int M = Integer.parseInt(tokens[1]);
		List<String> lines = new ArrayList<>(M);
		for (int i = 0; i < M; ++i) {
			lines.add(in.readLine());
		}
		in.close();
		Main ins = new Main(N, M, lines);
		System.out.println(ins.result);
	}
}