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();
		boolean[] ans=new boolean[n];
		Unionfind uf=new Unionfind(n);
		for(int i = 0; i<m; i++){
			int x = sc.nextInt()-1;
			int y = sc.nextInt()-1;
			int z = sc.nextInt();
			uf.unite(x,y);
		}
		long count=0;
		for(int i=0; i<n; i++){
			if(!ans[uf.root(i)]){
				ans[uf.root(i)]=true;
				count++;
			}
		}
		System.out.println(count);
	}
	static class Unionfind{
		int[] parent;
		public Unionfind(int n){
			this.parent=new int[n];
			for(int i = 0; i<n; i++){
				parent[i]=i;
			}
		}
		public int root(int t){
			if(parent[t]==t){
				return t;
			}else{
				return parent[t]=root(parent[t]);
			}
		}
		public void unite(int x,int y){
			if(same(x,y)){
				return;
			}
			int xroot = root(x);
			int yroot = root(y);
			parent[yroot]=xroot;
		}
		public boolean same(int x,int y){
			return root(x)==root(y);
		}
	}
}
