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.Arrays;
import java.util.Scanner;
import java.util.stream.IntStream;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int N = sc.nextInt();
        int M = sc.nextInt();
        int[] X = new int[M];
        int[] Y = new int[M];
        int[] Z = new int[M];
        for (int i = 0; i < M; ++i) {
            X[i] = sc.nextInt() - 1;
            Y[i] = sc.nextInt() - 1;
            Z[i] = sc.nextInt();
        }

        System.out.println(solve(N, X, Y, Z));

        sc.close();
    }

    static int solve(int N, int[] X, int[] Y, int[] Z) {
        int[] parents = new int[N];
        Arrays.fill(parents, -1);

        for (int i = 0; i < X.length; ++i) {
            int rootX = findRoot(parents, X[i]);
            int rootY = findRoot(parents, Y[i]);
            if (rootX != rootY) {
                parents[rootY] = rootX;
            }
        }

        return (int) IntStream.range(0, N).map(i -> findRoot(parents, i)).distinct().count();
    }

    static int findRoot(int[] parents, int node) {
        int root = node;
        while (parents[root] != -1) {
            root = parents[root];
        }

        int p = node;
        while (p != root) {
            int next = parents[p];
            parents[p] = root;

            p = next;
        }

        return root;
    }
}