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 {
    private static int[] p;
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int M = sc.nextInt();

        p = new int[N];
        for (int i = 0; i < N; i++) {
            p[i] = i;
        }

        for (int i = 0; i < M; i++) {
            int X = sc.nextInt()-1;
            int Y = sc.nextInt()-1;
            int Z = sc.nextInt();
            unite(X, Y);
        }

        Set<Integer> set = new HashSet<>();
        for (int i = 0; i < N; i++) {
            set.add(root(i));
        }

        //System.out.println(Arrays.toString(p));
        System.out.println(set.size());
    }

    private static int root(int x) {
        if (p[x] == x) {
            return x;
        }

        p[x] = root(p[x]);

        return p[x];
    }

    private static void unite(int x, int y) {
        int rootX = root(x);
        int rootY = root(y);
        p[rootY] = rootX;
    }
}

