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.BufferedReader;
import java.io.InputStreamReader;

public class Main {
    public static void main(String args[]) throws Exception{
        BufferedReader stdR = new BufferedReader(new InputStreamReader(System.in));
        String[] str = stdR.readLine().split(" ");
        int N = Integer.parseInt(str[0]);
        int M = Integer.parseInt(str[1]);
        
        int[] st = new int[M];
        int[] en = new int[M];
        for(int i = 0 ; i < M ; i++){
            str = stdR.readLine().split(" ");
            st[i] = Integer.parseInt(str[0]) - 1;
            en[i] = Integer.parseInt(str[1]) - 1;
        }
        
        int[] number = new int[N];
        int[] rank = new int[N];
        for(int i = 0 ; i < N ; i++){
            number[i] = i;
        }
        
        for(int i = 0 ; i < M ; i++){
            int a = numberuni(number, st[i]);
            int b = numberuni(number, en[i]);
            if(a == b)continue;
            if(rank[a] < rank[b]){
                number[a] = b;
            }else{
                number[b] = a;
                if(rank[a] == rank[b])rank[a]++;
            }
        }
        
        int count = 0;
        for(int i = 0 ; i < N ; i++){
            if(number[i] == i){
                count++;
            }
        }
        System.out.println(count);
    }
    
    public static int numberuni(int[] nums,int x){
        if(nums[x] == x){
            return x;
        }else{
            return numberuni(nums,nums[x]);
        }
    }
}
