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.Scanner;

public class Main{
	public static void main(String[] args) {
		Scanner sc =  new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		int input1,input2;
		int[] roots = new int[n+1];
		Calc calc = new Calc();

		//1行ずつ読み込み
		for(int i=0;i<m;i++) {
			input1 = sc.nextInt();
			input2 = sc.nextInt();
			sc.nextLine();

			if(roots[input1] == 0) {
				if(calc.searchRoot(roots,input2) != input1)
					roots[input1] = input2;
			}else {
				if(roots[input2] == 0) {
					if(calc.searchRoot(roots,input1) != input2)
						roots[input2] = input1;
				}else {
					int root1 = calc.searchRoot(roots,input1);
					if(root1 != calc.searchRoot(roots,input2)) {
						roots[root1] = input2;
					}
				}
			}
		}
		sc.close();

		int count = 0;
		for(int i=1;i<=n;i++) {
			count += (roots[i] == 0) ? 1:0;
		}
		System.out.println(count);
	}
}



class Calc{
	int searchRoot(int[] roots,int x) {
		if(roots[x]==0)
			return x;
		else
			return searchRoot(roots,roots[x]);
	}
}