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.util.HashSet;
import java.util.StringTokenizer;


public class Main{

	public static void main(String[] args) throws IOException {
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer in=new StringTokenizer(br.readLine());
        int N =Integer.parseInt(in.nextToken());
        int M =Integer.parseInt(in.nextToken());
        in = null;
		int[] arr = new int[N+1];
		HashSet<Integer> rootNodes = new HashSet<Integer>();

		for (int i = 0; i < M; i++) {
			in=new StringTokenizer(br.readLine());
			int x = Integer.parseInt(in.nextToken());
			int y = Integer.parseInt(in.nextToken());
			in = null;
			union(arr, x, y);
		}
		br = null;
		for (int i = 1; i <= N; i++) {
			rootNodes.add(find(arr, i));
		}
		System.out.print(rootNodes.size());
	}

	static int find(int[] parent, int i) {
	    while (parent[i] != 0) {
	        i = parent[i];
	    }
	    return i;
	}

	static void union(int[] parent, int x, int y) {
	    int xset = find(parent, x);
	    int yset = find(parent, y);
	    if (xset != yset) {
	    	if (xset <= yset) {
	    		parent[xset] = yset;
	    	}	else {
	    		parent[yset] = xset;
	    	}

	    }
	}

}