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.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.StringTokenizer;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Washoum
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        inputClass in = new inputClass(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        E1Or2 solver = new E1Or2();
        solver.solve(1, in, out);
        out.close();
    }

    static class E1Or2 {
        static E1Or2.Node[] graph;
        static boolean[] visited;

        static void dfs(int a) {
            visited[a] = true;
            for (int i : graph[a].edges) {
                if (!visited[i]) {
                    dfs(i);
                }
            }
        }

        public void solve(int testNumber, inputClass sc, PrintWriter out) {
            int n = sc.nextInt();
            int m = sc.nextInt();
            int[] x = new int[m];
            int[] y = new int[m];
            int[] z = new int[m];
            graph = new E1Or2.Node[n];
            for (int i = 0; i < n; i++) {
                graph[i] = new E1Or2.Node();
                graph[i].edges = new ArrayList<>();
            }
            visited = new boolean[n];
            for (int i = 0; i < m; i++) {
                x[i] = sc.nextInt() - 1;
                y[i] = sc.nextInt() - 1;
                z[i] = sc.nextInt();
                graph[x[i]].edges.add(y[i]);
                graph[y[i]].edges.add(x[i]);
            }
            int ans = 0;
            for (int i = 0; i < n; i++) {
                if (!visited[i]) {
                    dfs(i);
                    ans++;
                }
            }
            out.println(ans);
        }

        static class Node {
            ArrayList<Integer> edges;

        }

    }

    static class inputClass {
        BufferedReader br;
        StringTokenizer st;

        public inputClass(InputStream in) {

            br = new BufferedReader(new InputStreamReader(in));
        }

        public String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

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

    }
}

