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.Scanner;
class UnionFind{
    private int[] p, rank;
    public UnionFind(int n){
        p = new int[n];
        rank = new int[n];
        for(int i = 0; i < n; i++)
            p[i] = i;
    }
    public int findSet(int i){
        if(p[i] == i)
            return i;
        else
            return findSet(p[i]);
    }
    public boolean isSameSet(int i, int j){
        return findSet(i) == findSet(j);
    }
    public void unionSet(int i, int j){
        if(!isSameSet(i, j)){
            int x = findSet(i), y = findSet(j);
            if(rank[x] > rank[y])
                p[y] = x;
            else{
                p[x] = y;
                if(rank[x] == rank[y])
                    rank[y]++;
            }
        }
    }
}
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();
        UnionFind union = new UnionFind(n);
        int a, b, z;
        boolean[] know = new boolean[n];
        for (int i = 0; i < m; i++) {
            a = sc.nextInt();
            b = sc.nextInt();
            z = sc.nextInt();
            union.unionSet(a - 1, b - 1);
        }
        int total = 0;
        for(int i = 0; i < n; i++){
            int rank = union.findSet(i);
            if(!know[rank]){
                total += 1;
                know[rank] = true;
            }
        }
        System.out.println(total);
    }
}