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 static java.lang.System.*;
import java.util.*;

class UnionFind {
    int[] par;
    int[] num;

    UnionFind(int n) { 
    	par = new int[n];
    	num = new int[n];
        for(int i = 0; i < n; i++) {
        	par[i] = i;
        	num[i] = 1;
        }
    }

    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) return; 

        par[rx] = ry;
        num[ry] += num[rx];
    }

    boolean same(int x, int y) {
        int rx = root(x);
        int ry = root(y);
        return rx == ry;
    }

    int getNum(int n) {
    	return num[root(n)];
    }
}

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(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()-1;
			int y = sc.nextInt()-1;
			int z = sc.nextInt();
			uf.unite(x, y);
		}
		
		HashSet<Integer> set = new HashSet<Integer>();
		for(int i=0; i<n; i++) set.add(uf.root(i));
		
        out.println(set.size());
    }
}
