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 {
  static int[] par;
  static int[] rank;
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    par = new int[n];
    rank = new int[n];

    int M = sc.nextInt();
    init(n);
    
    for(int i = 0; i < M; i++) {
      int x = sc.nextInt() - 1;
      int y = sc.nextInt() - 1;
      int z = sc.nextInt();
      unite(x, y);
    }
    HashSet<Integer> set = new HashSet<Integer>();
    for(int i = 0; i < n; i++) {
      set.add(find(i));
    }
    System.out.println(set.size());
  }
  static void init(int m) {
      for(int i = 0; i < m; i++) {
        par[i] = i;
        rank[i] = 1;
      }
  }
  static int find(int x) {
      if(par[x] == x) {
        return x;
      } else {
        return par[x] = find(par[x]);
      }
  }
  static void unite(int x, int y) {
      x = find(x);
      y = find(y);
      if(x == y) return;

      if(rank[x] < rank[y]) {
        par[x] = y;
      } else {
        par[y] = x;
        if(rank[x] == rank[y]) rank[x]++;
      }
  }
  static boolean same(int x, int y) {
      return find(x) == find(y);
  }
}