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.*;
public class Main {

	public static class unionfind{
		int[] parent;
		int[] rank;
		int[] size;
		public unionfind(int n){
			this.parent = new int[n+1];
			this.rank = new int[n+1];
			this.size = new int[n+1];
			for(int i = 1; i <= n; i++) set(i);
		}
		public void set(int i) {
			parent[i] = i;
			rank[i] = 0;
			size[i] = 1;
		}
		public int find(int i) {
			if (i == parent[i])
				return parent[i];
			else
				return parent[i] = find(parent[i]);
			
		}
		public boolean same(int x, int y){
			return find(x) == find(y);
		}
		public void unite(int x, int y) {
			int xroot = find(x);
			int yroot = find(y);
			if(xroot == yroot)
				return;
			if(rank[xroot] > rank[yroot]) {
				parent[yroot] = xroot;
				size[xroot] += size[yroot];
			}
			else if(rank[xroot] < rank[yroot]) {
				parent[xroot] = yroot;
				size[yroot] += size[xroot];
			}
			else {
				parent[yroot] = xroot;
				size[xroot] += size[yroot];
				rank[xroot]++;
			}
		}
		public int getsize(int i) {
			return size[find(i)];
		}
		public int groupnum() {
			Set<Integer> parents = new HashSet<>();
			for(int i = 1; i < this.parent.length; i++)
				parents.add(find(i));
			return parents.size();
		}
	}
	
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int M = sc.nextInt();
		unionfind u = new unionfind(N);
		int ans = 0;
		for(int i = 0; i < M; i++) {
			u.unite(sc.nextInt(), sc.nextInt());
			sc.nextInt();
		}
		System.out.println(u.groupnum());

	}

}