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.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Queue;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int M = sc.nextInt();

		List<List<Integer>> card = new ArrayList<>();

		for(int i = 0 ; i < N ; i++){
			card.add(new ArrayList<>());
		}

		for(int i = 0 ; i < M ; ++i){
			int u = sc.nextInt()-1;
			int v = sc.nextInt()-1;
			int w = sc.nextInt();

			card.get(u).add(v);
			card.get(v).add(u);
		}

		sc.close();

		int ans = 0;
		boolean[] magic = new boolean[N+1];
		Arrays.fill(magic, false);

		for(int i = 0 ; i <  N ; i++){
			if(magic[i]){
				continue;//チェック済
			}

			magic[i] = true;
			ans ++;

			Queue<Integer> queue = new ArrayDeque<>();
			//未チェックのものをqueue.add
				queue.add(i);
			while(!queue.isEmpty()){
				int tmp = queue.poll();

					//pollした値とペアになっている数値をすべて確認

				for(int k = 0 ;k<card.get(tmp).size();k++){
					int tmp2 = card.get(tmp).get(k);
						if(magic[tmp2]){
							continue;
						}
				//つながっていればtrue
				magic[tmp2] = true;
				queue.add(tmp2);
				}
			}
		}
		System.out.println(ans);
	}
}
