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.Arrays;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class Main {
	static class UF{
		int[] par;
		UF(int N){
			par = new int[N];
			for(int i = 0 ; i < N ; ++i){
				par[i] = i;
			}
		}
		int root(int x){
			if(par[x] == x){
				return x;				
			}
			return par[x] = root(par[x]);
		}
		void unite(int x , int y){
			int rx = root(x);
			int ry = root(y);
			if(rx != ry){
				par[rx] = ry;
			}
		}
	}
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int M = sc.nextInt();
		UF uf = new UF(N);
		for(int i = 0 ; i < M ; ++i){
			int X = sc.nextInt() - 1;
			int Y = sc.nextInt() - 1;
			int Z = sc.nextInt() - 1;
			uf.unite(X, Y);
		}
		Set<Integer> s = new HashSet<Integer>();
		for(int i = 0 ; i < N ; ++i){
			s.add(uf.root(i));
		}
		System.out.println(s.size());
	}
}
