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.HashSet;
import java.util.Scanner;

class UnionFind{
	int[] par;
	int N;
	public UnionFind(int n){
		N = n;
		par = new int[N];
		for(int i = 0; i < N; i++){
			par[i] = i;
		}
	}
	public int find(int x){
		if(par[x] == x) return x;
		return par[x] = find(par[x]);
	}
	public Boolean same(int x, int y){
		return find(x) == find(y);
	}
	public void unite(int x, int y){
		if(find(x) == find(y)) return;
		par[find(x)] = find(y);
	}
	public int DistinctElementsNum(){
		HashSet<Integer> set = new HashSet<Integer>();
		for(int i = 0; i < N; i++){
			find(i);
			set.add(find(i));
		}
		return set.size();
	}
}


class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int M = sc.nextInt();
		UnionFind uf = new UnionFind(N);
		for(int i = 0; i < M; i++) {
			int X = sc.nextInt();
			int Y = sc.nextInt();
			int Z = sc.nextInt();
			uf.unite(X - 1, Y - 1);
		}
		System.out.println(uf.DistinctElementsNum());
	}
}