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.io.PrintWriter;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class Main {
    public static void main(String[] args) {
        try (InputReader in = new InputReader(); PrintWriter out = new PrintWriter(System.out)) {
            new Main().solve(in, out);
            out.flush();
        }
    }

    int[] rootFrom;

    private void solve(InputReader in, PrintWriter out) {
        int n = in.nextInt();
        int m = in.nextInt();

        rootFrom = new int[n];
        for (int i = 0; i < n; i++) {
            rootFrom[i] = i;
        }

        for (int i = 0; i < m; i++) {
            int x = in.nextInt() - 1;
            int y = in.nextInt() - 1;
            int z = in.nextInt();

            unite(x, y);
        }

        Set<Integer> ansSet = new HashSet<>(n);
        for (int i = 0; i < n; i++) {
            ansSet.add(calcRoot(i));
        }

        out.println(ansSet.size());
    }

    int calcRoot(int node) {
        if (rootFrom[node] == node) {
            return node;
        }

        rootFrom[node] = calcRoot(rootFrom[node]);
        return calcRoot(rootFrom[node]);
    }

    void unite(int x, int y) {
        int xroot = calcRoot(x);
        int yroot = calcRoot(y);

        rootFrom[xroot] = yroot;
    }
}

class InputReader implements AutoCloseable {
    private final Scanner sc = new Scanner(System.in);

    String next() {
        return this.sc.next();
    }

    int nextInt() {
        return Integer.parseInt(this.sc.next());
    }

    long nextLong() {
        return Long.parseLong(this.sc.next());
    }

    double nextDouble() {
        return Double.parseDouble(this.sc.next());

    }

    @Override
    public void close() {
        this.sc.close();
    }
}
